V85s 
 
 Young 
 
 A Study of Mine Surveying 
 
 Methods and Their Applications 
 
 to Mining Engineering
 
 THE LIBRARY 
 
 OF 
 
 THE UNIVERSITY 
 OF CALIFORNIA 
 
 LOS ANGELES 
 
 KALPH D. REED UBflARY 
 
 W>S ANGELES. CALIF.
 
 A Study of 
 
 
 
 Mine Surveying Methods 
 
 And Their Applications to 
 
 Mining Engineering 
 
 L E. (YOUNG, E. M. 
 Golden, Col. 
 
 THE IOWA ENGINEER 
 1904
 
 COPYRIGHT, 1904 
 
 BY 
 L. E. YOUNG 
 
 Republican Printing Company 
 Cedar Rapids, Iowa
 
 A STUDY OF MINE SURVEYING METHODS AND 
 
 THEIR APPLICATIONS TO MINING 
 
 ENGINEERING 
 
 By L. E. YOUNG 
 
 INTRODUCTION. 
 
 These notes, problems and observations have been compiled 
 in order to present in useful form for the student much that is 
 today scattered among various texts on surveying and much 
 from practical work that is not included in the average series of 
 lectures on mine surveying. 
 
 The surveying of lode and placer claims has been omitted, 
 as the present methods of conducting such work are very differ- 
 ent from practice in underground work, and recent legislation 
 ha's caused considerable confusion in all mineral surveys. 
 
 Mine surveying is really one part of mining engineering. 
 The purpose of these notes is to show how mine surveying enters 
 into all the other phases of mining engineering and what meth- 
 ods are best adapted to each kind of work. . 
 
 It is assumed that the student has a good knowledge of the 
 instruments and methods of plane surveying. He should be 
 skillful in handling and adjusting the various instruments. In- 
 struction in the art of adjusting the transit as used in mining 
 work should be given before underground work is attempted 
 
 DEFINITION. 
 
 The following definition is included in the introduction to 
 Johnson's "Theory and Practice of Surveying": "Surveying 
 is the art of making such field observations and measurements 
 as are necessary to determine positions, areas, volumes, or 
 movements on the earth's surface. The field operations em- 
 ployed to accomplish any of these ends constitute a survey. 
 Accompanying such survey there is usually the field record, 
 the computation, and the final maps, plats, profiles, areas, or 
 volumes. The art of making all these belongs, therefore, to the 
 subject of surveying." 
 
 Mine surveying is generally defined as the art of making 
 such measurements as may be necessary (a) to determine the 
 location and extent of bodies of coal, ore, etc., (b) to determine 
 the relative positions of points in the mine with regard to each 
 other or to points on the surface. 
 
 894803
 
 / A STUDY OF MINE SURVEYING METHODS 
 
 IMPORTANCE. 
 
 A. In all surveys the importance and the accuracy of con- 
 ducting the work should be directly proportional. The great 
 value of our mineral deposits and their limited extent war- 
 rant and demand the greatest care in establishing boundaries 
 and in conducting underground surveys. An example of this 
 fact is often seen in errors in surveying lode claims. A foot 
 increased length on the line of a lode three feet wide and con- 
 taining ore worth twenty-five dollars a ton, (fifteen cubic 
 feet per ton) represents for each thousand feet in depth on the 
 lode a value of five thousand dollars. 
 
 B. Pillars of sufficient size and propertly located must be 
 left in the mine either permanently or temporarily in order to 
 protect important passages, to prevent the inrush of water and 
 to protect adjoining property or buildings on the surface. 
 
 C. Royalties are often based on the underground surveys. 
 Stopes and working places must be accurately measured to de- 
 termine the volume of the excavation. From these figures the 
 tonnage removed is estimated. 
 
 D. Before any permanent openings are made, complete 
 surveys -should be made in order to determine the most ad- 
 vantageous site. The best location for a shaft, slope or tunnel, 
 and the best methods of exploitation, drainage, underground 
 transportation, hoisting, ventilation, etc., depend on the knowl- 
 edge of the deposit given by careful surveys. 
 
 E. In order to avoid breaking into old workings, where 
 there may be quantities of gas or water, good surveys and 
 maps are necessary. Many states require the filing of maps of 
 mines that are about to be abandoned. When driving openings 
 towards such workings, the proximity to dangerous ground can 
 be determined by careful survey. 
 
 F. Geological features and irregularities discovered by 
 drill holes or openings, when properly recorded and mapped, 
 may be anticipated. 
 
 G. Buildings, tracks, reservoirs, streams, etc., may be 
 properly protected if the openings are properly mapped. 
 
 H. Many mine surveying problems occur that demand 
 great exactness ; for instance, to determine a point on the sur- 
 face directly above a given point underground, in order that a 
 bore hole or shaft may be sunk to connect the former with 
 the latter. 
 
 I. A system of bore holes or drifts, an examination of 
 samples from the body blocked out and a complete survey will 
 permit of the estimation of the value of a mine or mineral deposit.
 
 AND THEIR APPLICA TIONS TO MINING ENGINEERING j 
 
 J. Much litigation may be avoided if the mine is properly 
 surveyed. 
 
 From these few statements the importance of mine survey- 
 ing is obvious. An inaccurate survey is valueless, in fact a poor 
 survey is often worse than none, in that openings may be driven 
 in the wrong direction to make connections, old workings may 
 oe tapped, etc. One of the essential things for a mine surveyor 
 to appreciate is the accuracy demanded of him. 
 
 DIFFICULTIES. 
 Many difficulties characterize mine surveying: 
 
 A. The surveyor is frequently called upon to carry a line 
 through low, narrow places where it is difficult to set up the 
 transit, take sights and measure distances. Coal seams twenty- 
 eight inches thick are frequently mined ; veins even narrower are 
 mined and often stations must be established and surveys made 
 in openings not more than twenty-eight inches high. 
 
 B. Artificial light is necessary in order to illuminate the 
 point of sight and the cross hairs. Such light is generally very 
 poor, and this fact greatly hampers work with the instrument. 
 When the safety lamp is necessary, the candle power is reduced 
 to less than unity. 
 
 C. A smoky atmosphere greatly reduces the possible 
 length of sight and often compels the surveying squad to post- 
 pone the survey. Sights of over two thousand feet are possible 
 in good air, but when the powder smoke is dense thirty feet is 
 a good sight. 
 
 D. In surveying highly inclined openings it becomes nec- 
 essary to use an auxiliary telescope to read vertical angles, to 
 measure inclined distances, and to calculate horizontal distances 
 and differences in elevation. 
 
 E. It is not always possible to make a closed survey, so 
 that the advantage of having a closed check is lost. This neces- 
 sitates repeating angles and remeasuring distances for all accur- 
 ate work. 
 
 F. The actual underground conditions frequently necessi- 
 tate the establishing of stations in the roof instead of in the 
 floor and setting up the transit under a point instead of over 
 a point. 
 
 G. The survey must be conducted so as not to interfere 
 with mining operations. This requires that the work be con- 
 ducted rapidly and at the same time accurately. 
 
 Methods of conducting underground surveys vary greatly ; 
 in England methods are still in vogue which have long since 
 been abandoned in America. The methods in the United States 
 depend largely on the value of the deposit and the proximity of 
 other workings.
 
 6 A STUDY OF MINE SURVEYING .METHODS 
 
 NOTES ON HISTORY. 
 
 A history of mine surveying would be composed largely of a 
 record of the evolution of mine surveying instruments. Such a 
 record has been recently compiled by D. D. Scott and others 
 and published in the Transactions of the American Institute of 
 Mining Engineers, Volumes XXVIIPXXXI. A few of the 
 more important points given in this record follow. 
 
 "Mine surveying, in some form or other, has been prac- 
 ticed from the earliest times ; but it has never kept pace with the 
 other branches of surveying, or even with the art of mining it- 
 self, and cannot be recognized as an exact science until shortly 
 after the beginning of this century." 
 
 1556 A. D. Agricola, in his De Re Metallica describes the 
 practice of mine-surveying. The instruments used were very 
 crude, the principal one being the stationary compass. 
 
 1571. Diggs describes the "theodolitus," also applies the 
 principle of the telescope. 
 
 1633. Rossler invented the method of suspending from 
 a cord a compass and clinometer. 
 
 1681. Houghton describes the use of strings, plumbs and 
 compass. 
 
 1686. Geometria Subterrania, of Nicholas Voigtel (Eisle- 
 ben, Saxony, 1686) exhibits slight development in methods and 
 instruments for mine surveying. 
 
 1710. Strum proposed the astrolabium for the miner. 
 
 1775. Kastner designed the quadrant clinometer. 
 
 1785. Beyer describes the common hanging compass. Tri- 
 pod came into use. 
 
 1798. Breithaupt introduced mine theodolites-. 
 
 1820. First American transit manufactured. 
 
 1843. Bourne first used high class theodolite in tunnel 
 work. 
 
 1850. First American mine transit. Top telescope first 
 used. 
 
 1858. Shifting tripod head successfully used. 
 
 1873. Coxe describes plummet lamp used in anthracite 
 coal mine. 
 
 1874. Coxe describes five hundred foot steel tape used in 
 coal mine surveying. 
 
 GENERAL STATEMENT OF INSTRUMENTS AND 
 EQUIPMENT USED. 
 
 A. Transit. The instrument should be selected with ref- 
 erence to the work to be done. The regular light mountain 
 transit, equipped with auxiliary telescope and mounted on an
 
 AND THEIR A F FLIC A TIONS TO .MINING ENGINEERING 7 
 
 extension tripod is commonly used. For careful work, the 
 instrument should have a complete vertical circle. A complete 
 description of mining transits is given in the volume of Scott 
 and others on "Mine "Surveying Instruments." The transit 
 should be equipped with a reflector and at times with a prismMic 
 occular. 'U 
 
 B. Compass. The compass, by means of which the first 
 surveys were made and which is still in use in many districts, 
 cannot be relied upon for accurate work especially in prox- 
 imity to bodies of iron or iron ore. Lupton in his "Practical 
 Treatise on Mine Surveying" published 1902, says in regard to 
 practice in English mines: "The dial is the instrument generally 
 used by mining surveyors for taking bearings and angles. The 
 graduated circle is stationary and the needle swings clear of "it. 
 Dials are made of various sizes, from a small pocket one up to 
 one carrying a needle eighteen inches long. The circle is 
 divided into degrees, and if the end of the needle is not opposite 
 one of the divisions, the surveyor has to estimate as nearly as 
 he can the fraction of the degree beyond the last unit, thus, %, %, 
 %, %, %, %, and % ; the bearing being, say southeast 21%". 
 
 However, in the United States, the compass survey is prac- 
 tically obsolete, many transists being constructed without the 
 compass. The compass reading serves as a check to detect er- 
 rors of more than one degree. For making a rough plat of a 
 mine, the compass is, however, of great use. Many so called 
 hand transists which resemble the English dial are used for 
 making such plats. 
 
 C. Level and Rod. The ordinary engineer's or wye level 
 is used underground in determining the elevation of points. 
 When the survey is properly conducted with the transit, vertical 
 distances are measured and it becomes unnecessary to carry 
 elevation by the level. Frequently the level is used in setting 
 timbers, sleepers, machinery, etc. The level should be mounted 
 on a heavy, adjustable tripod for precise work. 
 
 The rod used may be the regular five foot one which can 
 be extended to nine feet. The target should be so constructed 
 that it can be easily illuminated. Johnson suggests that "a 
 small steel rod like a knitting needle may be soldered onto the 
 target at the zero line so as to project two or three inches, then 
 a paper and light held behind it properly will enable the target 
 to be set." 
 
 D. Tapes. In mine surveying in the United States the 
 chain is practically obsolete. References are made in recent 
 articles to its use, but the work done with the steel tape is much 
 more accurate. A TOO foot steel tape divided into tenths and 
 hundredths of a foot is most generally used by American engin-
 
 8 A STUDY OF MINE SURVEYING METHODS 
 
 eers. Mr. E. B. Coxe was the first to introduce the long steel 
 tape or chain tape, at first 500 feet long, afterwards up to 1000 
 feet. Many tapes, 100 feet long, are graduated to feet through- 
 out their entire length and to hundredths only from o to 10 and 
 fom 90 to loo. In the anthracite fields tapes 310 feet long have 
 brcn used. The tape is so graduated that beginning at one end, 
 the marks are 10, 9, 8, 7, to o and then increase up to 300 at the 
 other end. Tapes 300 to 1000 feet long are of great advantage 
 in measuring long sights and also in measuring up working 
 places. 
 
 The length of tape and the graduation should be adapted to 
 the work. For important surveys, especially in establishing the 
 base line and carrying the meridian into the mine, a very good 
 tape should be used. It is never economy to purchase a cheap 
 tape. Errors are frequently traceable to the use of a poor 
 tape, and the cost or re-surveying any portion of a mine would 
 more than pay for a good tape. 
 
 In shaft work the tape should be of such a length that the 
 longest sights and distances can be measured without establish- 
 ing intermediate points. A 200 or 300 foot tape carefully grad- 
 uated should always be reserved for shaft work. 
 
 In traversing underground where long sights cannot be 
 made, a tape .more than 100 feet long is inconvenient. How- 
 ever, -when entries or levels are driven straight or "on line" long 
 tapes can be used to advantage. 
 
 For "measuring up" stopes and rooms long tapes should be 
 provided the length being determined by the regular system 
 of opening up the working places. In coal mines the rooms are 
 frequently from 200 to 300 feet long. In metal mines the levels 
 are seldom more than 200 feet apart and the stopes are there- 
 fore limited to 200 feet in height. These tapes need not be 
 graduated more than to feet. 
 
 Pocket tapes of 10 to 25 feet lengths should be carried by 
 the instrument man and the man who takes the side notes. The 
 instrument man must measure the height of instrument and of 
 the point, and should have a tape reading to hundredths. In 
 taking side notes it is generally not necessary to measure closer 
 than the tenths of a foot. 
 
 The standardizing of tapes is very important. If no stand- 
 ard is within easy access of the mine, the tapes should be sent 
 at regular intervals to some instrument maker to be compared 
 with the standard. In repairing tapes, it is very difficult to 
 restore the proper distance between graduations on opposite 
 sides of the break. It pays to send good tapes when broken to 
 those who make a business of repairing tapes.
 
 A\D THEIR APPLICA TIOXS TO AIIXIXG EXG1XEERIXG 9 
 
 Mine water frequently attacks tapes locally, thus causing 
 a reduction in the cross-sectional area. The tape hence becomes 
 weaker at such points and, if it does not break, will stretch 
 considerably if subjected to much tension. Such elongation 
 can be detected only by comparison with a standard. 
 
 Provision should be made for repairing a broken tape with- 
 out returning to the surface. Various types of clips or splices 
 can be made for this purpose, or can be obtained from instru- 
 ment companies. Such precautions may save considerable de- 
 lay. 
 
 Cleaning the tape is very necessary if the tape is to be 
 used in a mine producing acid water. Most mines produce 
 enough water to coat a tape with mud if the tape is not held off 
 the ground. Acid water if not speedily removed will soon 
 weaken the tape, and render it unfit for accurate work. Grit 
 and mud will, by abrasion, injure the tape in several ways. The 
 graduations will soon be worn away and the coiling of the tape 
 on a reel will give the grit opportunity to grind out deep notches. 
 The tape, then, must be carefully cleaned either underground or 
 on the surface. A preliminary cleaning should be given under- 
 ground, but this should always be succeeded by careful work on 
 the surface. One end of the tape should be attached to a fixed 
 point several feet above the ground and beginning at the end so 
 attached, the operation of removing the dirt and wiping dry 
 should proceed to the unattached end. After the tape has been 
 wiped drv. it should be rubbed with oil. Common kerosene 
 is generally used, but this is hardly of benefit. Sperm and olive 
 oil are recommended. 
 
 Reels of various types are used in mining work. It is 
 advisable to keep the tape out of the water and mud. and when 
 not in continuous service it is advisable to reel up the tape and 
 thus preserve it. Such reels may be of wood or metal, and 
 should be so constructed that the tape can be wound up without 
 binding, even when heavily coated with dirt. A convenient 
 form of reel is made of steel, of such design that the tape winds 
 on itself; across the back of the reel is a leather band or holder 
 through which the left hand is passed. Holding the reel in the 
 left hand the chainman easily winds up the tape by means of his 
 right. Care should be taken in removing the tape from the 
 reel as carelessness will result in breaking the end off the tape. 
 It is advisable to carry the tape into and out of the mine on a 
 reel. 
 
 Metal handles or clamps may be attached to the ends of the 
 tape or points intermediate in order to facilitate measuring. 
 Many engineers attach leather strips to the ends of tapes instead 
 of using the metal handles. In order to have uniformity of
 
 10 A STUDY OF MINE SURVEYING METHODS 
 
 tension in chaining spring balances may be used. In this way, 
 the tension being known, the amount of sag can be calculated. 
 
 The average tape used in mine surveying is graduated only 
 to feet. Some special device or method must be employed in 
 order to read the tenths and hundredths. Commonly in chain- 
 ing or measuring the tape is pulled up, the front chainman 
 marks the proper distance on the tape by means of his left 
 thumb, then reads the next foot mark toward the zero point, 
 and measures to his thumb by means of a short auxiliary tape. 
 Instead of marking with the thumb a metal clip may be used ; 
 this will witness the distance until measured with the small tape. 
 
 A convenient scheme is used by many engineers, by the use 
 of which marking clips and small tapes become unnecessary. A 
 strip of wood about one inch wide, one-eighth inch thick, and 
 about seven-tenths of a foot long is prepared. One end is cut 
 square and becomes the zero end. Measuring from this end, 
 tenths are laid off and notches cut as marks. In order to dis- 
 tinguish the zero end, the other end is rounded. Suppose the 
 distance between stations is between twenty-seven and twenty- 
 eight feet. The tape is drawn up, the thumb of the left hand 
 catches the point on tape and the strip of \vood is brought up 
 with the right hand and the distance from the point marked by 
 left hand to the nearest foot mark on tape is measured by the 
 stick. The tenths can then be easily read and the hundredths 
 estimated. This decimal of a foot will be either added to or 
 substracted from the \vhole number of feet depending on the 
 direction of measurement. The stick can be carried in a pocket 
 and can be easily replaced if broken or lost. 
 
 The zero point of the tape may be several feet from the 
 end. In the anthracite fields this length from zero to the end 
 is as much as 10 feet. These 10 feet are graduated regularly to 
 hundredths, the end of the tape being marked 10. From zero 
 to the other end, the tape is marked in feet. In measuring with 
 such a tape the rear chainman first holds the zero point of the 
 tape at the rear station so that the fore chainman can determine 
 the nearest 10 foot mark toward the rear chainman. That is, he 
 determines whether the distance between stations is between 
 no and 120 feet or 120 and 130 feet. If between no and 120, 
 he draws up the tape until no is at the front station, he then 
 calls "chain" to the rear chainman who reads on the extension 
 beyond the zero point the number of feet and hundredths which 
 must be added to 1 10. Thus auxiliary tapes, markers, etc., may 
 be avoided. 
 
 The measurement of distances should be checked in all 
 possible ways. Each party should measure distances twice. 
 When returning through newly surveyed openings, some mem-
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING // 
 
 her of the party should be detailed to pace distances and check 
 the measured ditances. When it is known that levels, entries 
 and rooms are driven a standard distance apart, calculations 
 should be made underground and measured distances thus 
 checked. 
 
 E. Bobs an Stations. The tools and equipment for locat- 
 ing, making and marking stations vary considerably and will be 
 described in detail later. Commonly, plumb bobs suspended from 
 stations in the roof by twine or wire give the point of sight. 
 Three bobs should be provided, one for the instrument, one for 
 the back sight and one for the fore sight. Ample string or 
 wire and other supplies should be provided for each day's work. 
 
 Miscellaneous. Note books must be provided for the 
 proper recording of all observations made. Books should be so 
 filed and work so recorded that any member of the engineering 
 corps can find and plat notes, or continue the work of any other 
 member. The notes of a transitman are generally taken as an 
 index of his work. Some field or pocket book sheuld be carried 
 by the party so that calculations may be made in the field if at 
 any time a check on the work is desired or if it becomes neces- 
 sary to set points properly for directing workmen in driving 
 openings or in locating timber, guides, etc. 
 
 A reading glass is necessary for the transitman, a sheet of 
 tracing cloth or oiled paper for those giving sights, a thermome- 
 ter if there be any marked increase of temperature in the lower 
 workings of a mine over that in the upper workings or of the 
 surface. Corrections in measurement should be made when the 
 temperature is high. An adjusting pin, screw driver, and sim- 
 ple repair kit should be included in the outfit of a party which 
 is going out for several days surveying. 
 
 SURVEYING PARTY. 
 
 Number. The number of men included in the party de- 
 pends entirely on the work to be done, the skill of the members, 
 and the time allowed for completing the work. Often, the 
 transitman only is experienced and must take as his assistants 
 so called "helpers" who know nothing of surveying. In order 
 to do measuring the party must consist of at least two. When a 
 mining company has sufficient work to keep one party in the 
 field continually, one or two men may assist the transitman. 
 In the anthracite field, surveying is done by parties of seven 
 divided into two squads one consisting of the chief and two 
 helpers who locate stations, measure distances and take side 
 notes, and the other party reads and records angles and dis- 
 tances. Parties of more than four are uncommon.
 
 is A STUDY OF MINE SURVEYING METHODS 
 
 Work of Members of Party. The chief of a party directs 
 the survey, establishes points, takes side notes, and checks dis- 
 tances. He must be able to plan and direct the work and 
 manage men. The transitman may be chief of party. He has 
 charge of the transit, reads and records angles and distances ; he 
 may take the side notes. He must be an accurate and rapid 
 worker. Accuracy, however, comes first, as inaccurate work is 
 valueless. 
 
 The fore sightman or fore chainman establishes stations, 
 numbers and marks the stations, gives the fore-sight, superin- 
 tends measuring, records distances, may keep side notes and 
 may be detailed to set up the instrument. He must be a good 
 conscientious worker and should take much pains and pride in 
 his work. 
 
 The back sightman gives backsights, assists in chaining, 
 carries any material to be carried, keeps all equipment save the 
 transit in good shape, cleans the tapes, makes plugs, etc., and 
 sharpens tools. He must be a good workman and should have 
 ambition to become the transitman. 
 
 Side notes may be taken by the chief of the party when the 
 party is divided into two squads, and by the transitman when 
 there is but one squad. If the fore sightman is competent, this 
 work may be assigned to him. The completeness of the mine 
 map depends largely upon the care with which the side notes 
 are taken, and such work should receive considerable attention. 
 By side notes are meant those additional measurements which 
 are taken off the traverses, by which points in adjacent excava- 
 tions are located with regard to the traverses. The dimensions 
 and location of openings are thereby determined. 
 
 Work of Party. A. The success of the party depends 
 largely upon the chief. He should understand men, have their 
 confidence, encourage them to learn the details and principles of 
 the work. He should be able to plan work so that the entire 
 party shall be busy and if possible have his assistants attend to 
 all details. He can then give his hill time to running the party 
 and doing transit work. 
 
 B. A good party is composed of men who will do more 
 than the actual work assigned and who realize the importance 
 of the details. Failure to provide daily the proper tools and 
 equipment, may render many hours work valueless or cause 
 considerable loss of time while the necessary equipment is being 
 provided. 
 
 C. Surveying work should not interfere with mining oper- 
 ations and vice versa. When properly planned and executeu, 
 the work may be carried along entries which are used for haul- 
 age without materially interfering with traffic. Smoke will
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 13 
 
 interfere with the work if the chief has not anticipated it and 
 transferred his work .to passages having a clear atmosphere. 
 The work can be properly planned so that the party shall have 
 completed the work in haulage ways or near working places 
 before cars or smoke can interfere. 
 
 D. Too much stress cannot be laid upon the importance 
 of subordination of all other members of the party to the chief. 
 The party must work toge'ther. The chief should enjoy the 
 most earnest co-operation of his men and should make them 
 appreciate that careful work and strict attention to all details 
 are necessary to good surveying. A few minutes given to 
 explanation of the importance and object of certain operations 
 may in the end save much time. Each man should be made to 
 realize that his welfare is being considered by the chief, thai 
 he is not obliged to do unnecessary work, or to remain in 
 strained positions an unwarranted length of time, and, especially, 
 that his time belongs entirely to the chief of squad. 
 
 E. A complete and practical system of signals should be 
 devised for underground work. Systems in vogue on the sur- 
 face are in general impracticable underground. In sighting and 
 measuring it is very important that the man at the instrument 
 or at one end of the tape should be able to communicate with 
 his co-laborer without walking or climbing to him. The move- 
 ment of a light or special sounds are commonly used to indicate 
 certain orders. However, where a number of lights are con- 
 tinually moving about, as in shaft sinking, the use of the light 
 as the signal is impossible. Again, the voice or a whistle cannot 
 be used in the proximity of noisy machinery. Frequently in 
 doing important work, especially in shafts, surveyors stretch a 
 chord or wire so that by movements of this chord one party 
 below may signal to another above or vice versa. Special sys- 
 tems may easily be devised to fit the occasion. 
 
 F. Special care should be taken with all notes. Notes 
 cannot be too full. The surveying party should note geological 
 features, character of mineral, thickness and character of coal 
 or other points which may later on be of value in planning 
 underground operations. It is much more economical to take 
 full and complete notes when making a survey than to be 
 obliged later on to make a special visit to determine these points. 
 By noting faults or horses in the upper workings, these can be 
 frequently anticipated in driving lower or adjacent openings. 
 All readings and measurements should be checked as often 
 as possible. Subordinates should be trained to check readings 
 for the instrument man. The foresightman should carry a note- 
 book and record measured distances even though he do not 
 take the side notes. Many calculations may be made in the
 
 // A STUDY OF MINE SURVEYING METHODS 
 
 field to check observations without interfering with actual work. 
 Frequently a few minutes spent in this. way will save several 
 hours work in correcting errors or making resurveys. 
 
 ' UNDERGROUND STATIONS. 
 
 The care with which a station should be established de- 
 pends upon the character of the survey and whether or not it is 
 to be considered a permanent station. Stations may be divided 
 into two groups (a) temporary, and (b) permanent. 
 
 By a temporary station is meant any station which will 
 probably be knocked out soon after being established or one 
 which is designed to serve only for the survey for which it is put 
 in. A permanent station is established carefully and precautions 
 are taken to have it so located and marked that it may serve 
 with similar points as a base or reference 10 vhich subsequent 
 surveys may be tied. 
 
 The inexperienced surveyor loses more time by making 
 poor stations and by marking them in a poor manner than by 
 making actual errors in the survey. The surveyor whose work 
 it is to keep a shaft or tunnel properly aligned or to keep the 
 mine man up to date should before beginning a survey check 
 up his newest stations to see that they have not been disturbed. 
 Very often the station mark has been removed, the station has 
 been tampered with, is inaccessible or has dropped out or been ' 
 completely destroyed. The experienced surveyor sees that he 
 has a number of stations so established that even though one is 
 destroyed, he suffers no great inconvenience. 
 
 i. The permanency of a station in the floor or bottom 
 depends upon (a) the marking, (b) the character of material, 
 (c) the hardness of ties, (d) the amount and kind of haulage, (e) 
 the character of the roof, (f) the character of the station it- 
 self or (g) the mine water. 
 
 a. In all cases the station which cannot be indentified is 
 worthless. To be of value or permanent the station in the 
 floor must be so marked that it can be easily found and identi- 
 
 b. A permanent station cannot be established in the floor 
 when the latter is composed of very soft material ; or, when 
 there is considerable pressure about the opening, the floor mater- 
 ial is forced up thus displacing the station. 
 
 c. Frequently stations are established in the ties. A 
 station in soft wood is practically valueless as a permanent mark 
 for it is easily loosened or displaced. 
 
 d. Unless protected in some way by a shield or covering, 
 a station in the floor of a roadway along which there is con- 
 siderable haulage is liable to be knocked out. This is espec-
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 75 
 
 ially true when the motive power is men or mules ; with rope or 
 locomotive haulage the station is more permanent. 
 
 e. The character of the roof must often be considered. If 
 the roof is very strong there is probability of the floor rising ; 
 if the roof is fragile considerable material falls and must be 
 removed. Stations in the floor of an entry in which there are 
 frequent falls may be knocked out by the men who shovel out 
 the rock. 
 
 f. The station to be permanent should consist of a nail 
 driven into a wooden plug firmly imbedded in the floor or of a 
 rivet firmly imbedded in the floor. Nails in ties or in cracks 
 in the floor can hardly be classed as permanent stations. 
 
 g. Stations established in the floor are liable to corrosion 
 by mine water. The metal may be entirely dissolved or various 
 materials may be deposited upon it. 
 
 h. Stations in the floor when near working places will be 
 loosened or blown out by shots. 
 
 The permanency of stations established in the roof depends 
 upon (a) the marking, (b) the character of roof, (c) the char- 
 acter of station, (d) workmanship, (e) mine water, (f) proximity 
 to workings, (g) character of floor. 
 
 b. When the roof is fragile, the station may drop out. 
 
 g. When the floor is soft, and there is considerable roof 
 pressure, material is forced up from the floor and the roof sinks 
 thus decreasing the elevation of the station or dropping it out 
 completely. 
 
 The permanency of a station established in timbers depends 
 upon (a) the permanency and character of the timber, (b) the 
 settling of the timber, (c) the character of the station, (d) mark- 
 ing, (e) the proximity to working places. 
 
 a. Stations placed in poor timbers or sets which may be 
 removed cannot be considered permanent, in fact most stations 
 in timber are temporary. 
 
 b. Timbers frequently settle considerable, especially when 
 the bottom is soft and no sill is used. 
 
 e. Timbers set near working places may be knocked down 
 by shots. 
 
 Stations may be established in timbers which must be locat- 
 ed in definite positions as shaft timbers. 
 
 In certain systems of mining, as longwall advancing, it is 
 almost impossible to keep stations in the roof, which fact is due 
 to the caving of the roof as the work advances. As longwall is 
 used in flat seams, horizontal angles alone must be measured. 
 The sinking of timber and the rising of the floor need not be
 
 16 A STUDY OF MINE SURVEYING METHODS 
 
 considered when no horizontal displacement of the station is 
 noted. Many engineers carry stations in the floor under such 
 conditions. 
 
 2. Stations should be so located that (a) the fewest num- 
 ber, necessary for the purpose, be used, and that (b) these be 
 at the most available and useful points. 
 
 a. Before locating stations it is advisable to inspect the 
 workings to determine the most advantageous points for sta- 
 tions. Short sights and unnecessary set-ups can often be 
 avoided by thus planning the work. Reference stations should 
 be established at convenient points in back entries so that haul- 
 age, etc. may not interfere with the work. At the intersection of 
 important roadways, good witness stations should always be 
 established because points at intersections are often knocked out. 
 
 Permanent stations should be located where there is little 
 danger of their being disturbed, not always at the most conven- 
 ient points. 
 
 3. Character of Station. 
 
 a. "The simplest top station is a shallow conical hole made 
 with the point of the foresightman's hatchet, which is dug into 
 the top rock and rotated ; it is called by some a jigger station. 
 Corps using these entirely have a jigger, consisting of a steel 
 pointed extension rod with an offset holding a paint brush. The 
 rod is long enough to allow the point to be driven into the roof 
 at any height, and its rotation marks a circle with the brush, 
 which is also used to mark the number beside the circle. Cen- 
 ters are set under such stations, and sights are given by another 
 tool also called a jigger. This is an extension rod, beyond the 
 upper end of which projects a sheet iron shaped like an isosceles 
 triangle, with the upper and smaller angle cut off so as to form 
 an end one quarter of an inch broad, and in this end is cut a TJ 
 shaped groove. The sights are given and "centers" set by put- 
 ting a plummet chord in this groove. The advantage of this 
 method lies in the rapidity with which the centers are set. and the 
 sights given, and the ease with which the highest stations are 
 reached. The disadvantages are the impossibility of making 
 the jigger hole perfectly conical, so that the jigger can be set 
 in the same place on two successive sights, and of making the 
 plummet chord hang in exactly the same place. "* 
 
 b. Common nails may be driven in cracks in the roof or 
 floor. AVhen the nail is driven in the roof a plumb line and bob 
 are suspended. When the nail is driven in the floor or tie, a 
 pencil or rod is placed vertically over the nail at which the in- 
 strument is sighted. 
 
 *f!oll. Eng. XIV, 10.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 77 
 
 c. Spads, spuds, staples or screw eyes may be driven into 
 a crack in the roof or into a timber. Spads or spuds are gen- 
 erally made by hammering- out the head of a horseshoe nail and 
 punching a hole in the flattened head for inserting the chord. 
 Iron or copper may be used for spads, but iron is generally used 
 because it cheaper. It is not advisable to make a station in a 
 crack, for the same force which made the crack may cause it 
 to open further and the station will then drop out. Such cracks 
 are generally water courses. tfoT 
 
 For accurate work nails should.be used because the plumb 
 line may be suspended from either side of the nail and in short 
 sights the error due to the width of a nail in backsight and 
 foresight will soon become quite appreciable. 
 
 d. A spad is driven into a wooden plug in the roof. Holes 
 from i YZ " to 6" in depth and of such diameter that the spad will 
 not split the plug driven into the hole are drilled in the roof at 
 the point selected. The smaller the hole the quicker the work. 
 Drilling may be by hammer and drill, twist drill or power drill. 
 When the roof is poor, it must be brushed down until it sounds 
 firm under the hammer. When the roof is too poor, a special 
 type of station may be put in or a timber may be cut in to support 
 the station temporarily and a permanent point may be establish- 
 ed near by. 
 
 The plug is of wood, of slightly larger diameter than the 
 hole, tapered at one end, sawed off square at the other, slightly 
 longer than the depth of hole, and driven up flush with the roof. 
 When wet the plug expands and fills the hole completely. The 
 wood should be hard enough to stand driving and to hold the 
 spad and should not split when the spad is driven. Good plugs 
 for small holes can be made from broom handles. Plugs and 
 spads should always be made on the surface. The spad should 
 be driven broadside to the line of sight. 
 
 e. A hole 3-32" in diameter may be drilled in the roof; 
 a cord or wire placed in the hole can be held firmly by a small 
 wooden plug driven in flush with the roof. A lamp or bob as 
 desired may be hung from the cord or wire. 
 
 f. A cylindrical hole may be drilled in the roof. A clip 
 made by bending back upon itself a band of thin steel 3-32" 
 wide having a hole drilled in the center of the clip may be placed 
 in the hole. The clip is so made that the cord passing through 
 the hole in the clip always hangs from the center of the hole in 
 the roof. After the observations are completed, the clip is 
 removed from the hole in the roof. The disadvantages of such 
 a station are important ones. The roof must be good or else 
 uniform holes cannot be driven. All holes should be of small 
 depth and circular in section. The clip cannot always be re-
 
 r8 A STUDY OF MINE SURVEYING METHODS 
 
 placed in the holes so that the line hangs in the same position as 
 at first. 
 
 g. Stations in the floor may be made by placing a ^" rivet 
 in a hole l / 2 " diameter and 2" deep. The end of the rivet is 
 split and a wedge of wood inserted in this split so that when 
 the rivet is driven into the hole it wedges fast. A mark made 
 on the rivet head gives the point for the station. 
 
 h. When the roof is so poor that' a station cannot be 
 established in it, three spads are driven in the wall near the 
 roof for the support of the following device.* In the center of a 
 sheet of galvanized iron, cut to form an equilateral triangle, base 
 i^4", is punched a small hole through which is hung a plumb 
 bob. To each corner of the triangle is attached a chain by 
 which the entire device may be hung from the three spads in 
 the walls. The chains are of equal length and must not stretch. 
 The spads should be so located that the plate will hang horizon- 
 tal and the plumb bob in the line of sight. The disadvantages 
 of such a station lie in the fact that three points must be pre- 
 served instead of one. The bending of the plate, the twisting 
 of the chain or the bending of the hooks by which the chains are 
 hung from the spads will prevent the hanging of the bob to 
 duplicate the first conditions. In low entries it is difficult to 
 manipulate this device so that the instrument can be easily set 
 up under the bob so suspended. The point of set-up may be 
 marked in the floor and the instrument set up over this point. 
 
 4. Marking of Stations.! 
 
 a. As previously stated a station so poorly marked that its 
 identity cannot be determined is valueless until it has again 
 been properly located. Temporary stations need not be mark- 
 ed very carefully as they are not designed to be of future benefit 
 to the one who establishes them. 
 
 b. In addition to being numbered or marked to distinguish 
 from other stations all stations should be so witnessed that they 
 can be readily found. 
 
 Mines and Minerals XIX, 247. 
 
 f A number of large and well managed mines do not mark the num- 
 ber of stations underground. All stations have a number which ap- 
 pears in the note book and on the maps. There may be cited an instance 
 of a mine operating three shafts over a thousand feet in depth. There 
 have been established over two thousand stations not one of which can 
 be identified by any one unfamiliar with the mine. It required a new 
 surveyor three months to learn the mine so that stations could be found. 
 Again in this same property station 121 may be on the first level and 
 station 122 on the eighth: station 2001 on the ninth and station 2002 on 
 the third. The mine officials appear to be well satisfied with this lack 
 of system.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING JQ 
 
 B. Place. Marks may be made (a) on the station itself, 
 (b) on the roof or walls, and (c) on the timber. 
 
 a. It is rather unwise to witness the station on itself; if the 
 station be destroyed there is no mark ; a better method can 
 easily be found. 
 
 b. In coal mines the roof is generally smooth and the walls 
 rough. In metal mines very often one or both walls are smooth 
 and the roof rough. In tunnels generally the walls and roof are 
 all rough. When walls and roof are equally firm, the smooth 
 surface is to be preferred. 
 
 c. Marking on timber depends on the permanency of tim- 
 ber and of the station. It is difficult to paint or mark on rough 
 timber ; however, dressed timber gives a good surface for any 
 kind of a mark. 
 
 C. Kind of Marking. 
 
 a. Paint. Some geometrical form enclosing the station or 
 number of the station may be used. When the station is in the 
 floor a vertical line is drawn on one of the walls opposite and the 
 station number enclosed in some geometrical form. The mark 
 used should distinguish the station from those of other surveys. 
 The color of the paint used depends upon the background. For 
 dark walls use white paint (white lead mixed with linseed oil) 
 and for white walls, as salt and gypsum, use dark paint. Suf- 
 ficent paint for the day should be carried in a quart tin can. A 
 round bristle brush about one inch in diameter and well wound 
 with wire in order to make it stiff enough for rough work is used 
 in applying the paint to the walls. When the walls are very wet, 
 paint is not to be recommended as it comes off quickly. 
 
 b. Chalk. When the instrument man marks stations 
 himself, which is generally when he desires only temporary 
 stations, chalk may be used on dry walls. 
 
 c. Nails and washers. At times numbers are made by 
 driving nails into timbers. A washer is used to denote zero. 
 Nails may be driven to outline figures or in rows composed of 
 the same number of nails as there are units in the digit. It is 
 rather inconvenient to use this system when the numbers are 
 large or where there is little timbering. 
 
 d. Tags. These are generally discs of brass, zinc or lead, 
 on which is stamped the mark for the station. The tag is 
 punched and through the hole is driven the spud or nail of the 
 station. It may be painted white to make it easily seen. Tags 
 made from sheet metal upon which the number is stamped may 
 be hung from the station. When the station drops out there 
 is no clew to its former position. 
 
 e. Figures chiseled in the wall. This mark is very per- 
 manent in good rock, and is the best for wet walls.
 
 20 A STUD Y OF MINE S UR VE YING ME THODS 
 
 All marks should represent good workmanship ; numbers 
 and letters should be easily legible. In some way they should 
 be distinguishable from marks of other surveys. 
 
 D. System of Marking. Marks to be of value must be 
 according to some system. The importance of having a good 
 system can be readily appreciated. When a party is daily es- 
 tablishing stations in various parts of a large mine, unless some 
 method is used in marking stations it will be necessary to have 
 a map of the mine at hand in order to locate a given station. 
 Again instead of the station identifying itself with regard to 
 location, the map must again be used. In large coal mines 
 openings cannot be readily identified unless stations or drifts 
 are intelligently marked according to some system. 
 
 a. Frequently, drifts or entries are named and the stations 
 on the drift are numbered consecutively towards the working 
 face. A station then may be marked Swede Drift 9. It is rath- 
 er awkward and laborious to put the name of the drift at each 
 station. 
 
 b. Openings may be lettered and stations numbered con- 
 secutively as in (a). A station then would be marked A 6, or 
 M 16, R 21, etc. 
 
 c. A section of a mine may be given a letter or a number ; 
 as all ground between certain boundaries would be A and 
 stations in that block numbered consecutively as A i, A 100, 
 etc. Levels of a mine may be lettered or all stations on a certain 
 level given a group number, as all stations on first level would 
 be 100 to 199, on the third 300 to 399, etc. 
 
 d. When drifts or openings are turned off at regular inter- 
 vals these may be numbered consecutively from some given 
 point and with regard to direction. Along a main entry run- 
 ning east and west, side entries north and south are distiguished 
 as first south or tenth north. Stations are numbered consecu- 
 tively on the main entry without prefix or suffix. On the side 
 entries we may number ioN25 or 2833 meaning station 25 on 
 the tenth entry to the north and station 33 on the second entry 
 to the south. In this way the station really locates itself. In- 
 stead of numbering the stations consecutively, distance from a 
 given point may be used. Suppose a station is 307.46 feet from 
 the main entry on the fifth south, the mark should be 583+07.46. 
 
 e. The system of numbering stations consecutively as they 
 are put in is very poor practice. By this method station 356 
 may be in one part of a mine and 357 in another part possible a 
 mile distant. 
 
 Various modifications of these systems may be adapted to 
 circumstances.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 21 
 
 5. Point of Sight. In surveying underground artificial 
 light is, of course, necessary both at the instrument and the point 
 sighted. Various devices have been used to illuminate the 
 point sighted. 
 
 a. Common practice is to use a light as the point of sight. 
 The point of light used depends largely upon the character of 
 the mine and what kind of light the miners use. In metallifer- 
 ous mines the tallow candle is used, in coal mines an open lamp 
 burning lard oil or the safety lamp. The acetylene and electric 
 lamps are sometimes used by mining engineers. When locating 
 points in rooms or stopes or at the breast of drifts, the light is 
 often sighted at instead of an established point. 
 
 b. A rod, nail or pencil properly illuminated may be used 
 for rough sights. When the side telescope is used, the double 
 or lop-sided target may be used instead of the ordinary rod or 
 plumb bob. The double target is so constructed that the point 
 sighted at on the target is not directly under the station but off 
 to one side a distance equal to the distance from the axis of the 
 side telescope to the station under which the instrument is set, 
 or equal -to the distance between telescopes. When such a 
 target is used no correction need be made for the side telescope. 
 
 c. A plumb line suspended from the station is the common 
 point of sight. The vertical wire of the instrument is set upon 
 the line or upon the point of the bob. In order to facilitate the 
 measurement of distance and to have uniformity in the work, it 
 is quite common to loop the line about a nail or a match so that 
 when the line is stretched taut by the weight of the bob the nail 
 or match will hang horizontal, thus giving a good point upon 
 which to set the horizontal wire. The vertical angle and meas- 
 urements to the instrument and to the roof and floor are taken 
 with regard to this point. To illuminate the line or bob suffi- 
 ciently a sheet of oiled paper or tracing cloth should be placed 
 in the line of sight back of the plumb line and back of the paper 
 the light. 
 
 d. In (a) it was suggested that the sight be taken at the 
 naked light, Mr. Coxe adapted the plummet lamp which consists 
 of-a heavy lamp suspended from two or three chains so that the 
 whole can be easily hung from an established point in the roof. 
 The lamp always hangs at the same distance below its point of 
 support. When the transitman is ready to sight, the lamp is 
 hung and lighted and the flame bisected by the vertical wire, the 
 horizontal wire being set upon the proper point of the lamp. 
 
 e. In the three tripod system the point of sight is again a 
 lamp but instead of being suspended from the roof it is sup- 
 ported on a tripod similar in every way to the one on which 
 the transit is set up.
 
 22 A STUDY OF MINE SURVEYING METHODS 
 
 f. Instead of having an illuminated background against 
 which the point of sight w r ill show plainly, the background may 
 be darkened and the line of sight illuminated. This is accom- 
 plished by cutting a horizontal and a vertical slit in a sheet of 
 metal and after the sheet has been placed so that the slit will 
 be in the proper line, the lamp placed behind the slit illuminates 
 the slit. 
 
 Vertical sheets of metal in the same plane and so mounted 
 that they can be easily shifted have been mounted on a plat- 
 form and placed behind wires used in shaft plumbing. By this 
 arrangement the sheets may be shifted so that a vertical line of 
 sight may be developed directly back of the wire sighted. 
 
 g. Various patent devices for sighting in underground 
 work have been put upon the market. One of the best of these 
 consists of a strip of sheet metal about 2" wide and 12" long. 
 At either end are cut holes so that the strip may be suspended 
 from the station by a cord and from the lower end of the strip 
 the plumb bob is hung. A number of holes are drilled in the 
 strip, the centers being on the line between the upper and lower 
 cords. Half w r ay between the ends of the strip, the hole drilled 
 is about y z " diameter, from the center towards each end the 
 holes diminish in diameter and are far enough apart so that there 
 remains between adjacent holes about */6" of metal. When a 
 
 -. light is placed behind the strip, the strip being at rest, a vertical 
 line of sight appears to the instrument man. He can also sight 
 at the plummet as it revolves, bisecting the ellipse of light in 
 the center. The different sizes of holes will suit long or short 
 distances by allowing more or less light to pass through. 
 
 BASE LINE. 
 
 T. A base or reference line should always be estimated or 
 selected before any attempt is made to carry the meredian un- 
 derground. It is always advisable to establish the meredian 
 before doing any underground surveying. If this be not done 
 it will always be necessary to correct bearings or later on to 
 change the entire set of field notes. The importance of having 
 such line is very obvious especially when several openings are 
 made on one property and it is necessary to survey for con- 
 nections. 
 
 2. Such a base line should be marked by permanent sta- 
 tions that will be accessible at all times if possible. In districts 
 in which the ground is covered deep with snow during manv 
 months in the year, points must be established where they will 
 not be covered very deep or where they can be found easily. 
 These points should be convenient to shafts or openings so that
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 23 
 
 sights to the same line can be taken from any opening. When 
 such arrangement cannot be made a trangulation system should 
 be laid out. 
 
 3. All uderground surveys of adjacent properties should 
 be referred to the same base and the same datum. Unless this 
 is done at once corrections will have to be made when connec- 
 tions between adjacent workings are calculated. Notes should 
 be taken in the same way and azimuth measured always from 
 the south or always from the north. 
 
 After the base line or reference system has been established, 
 some point or points should be located in or about the mouth 
 of the tunnel or collar of the shaft. About a tunnel this is 
 sometimes difficult because the ground adjacent will be graded, 
 or covered with waste rock, or the track arrangement may not be 
 permanent. Owing to the hoisting rope, sheave and dumps it 
 is almost impossible to locate a permanent point over a shaft. 
 This is especially true of vertical shafts. Timbers or pipes being 
 taken into the mine often knock out points. The engineer 
 should at once look over the ground and find some point adja- 
 cent to the shaft which will not be disturbed. 
 
 CARRYING THE LEVEL AND MERIDIAN INTO THE 
 MINE. 
 
 In order that underground points may be located with 
 regard to points on the surface it is essential that by some 
 means the meridian be carried into the mine. In other word's 
 a survey must be made from the surface through the openings 
 to points in the mine. Such an opening may include measur- 
 ing the depth of the shaft, plumbing the shaft or carrying the 
 line underground by direct sighting with the transit. 
 
 Levels. The depth of a shaft or opening may be deter- 
 mined. 
 
 (a) By the aneroid barometer when only a rough figure 
 is desired. Read the barometer at the surface, also noting the 
 temperature ; then go underground to the bottom and read the 
 barometer, noting temperature. The barometer reading should 
 be taken several times ; after the barometer reading is constant 
 return at once to the surface and again take several readings at 
 the surface. Corrections for difference in temperature between 
 the mine openings and the surface should be made. The mean 
 of the difference between reading taken at the surface and un- 
 derground is the depth of opening. 
 
 b. The depth of a vertical or inclined shaft of uniform dip 
 may be determined by measuring the length of the hoisting 
 rope used in reaching the bottom of the shaft. In order to do
 
 24 A STUDY OF MINE SURVEYING METHODS 
 
 this the number of revolutions of the head sheave during the 
 hoist should be noted. The circumference of the sheave being 
 known the amount of rope wound can be easily calculated, or 
 two marks can be made on the rope, one opposite a fixed point 
 when the cage or skip is at the bottom, another after the cage 
 or skip has been brought to surface, opposite the same point. 
 The rope between these marks represents the depth of the shaft. 
 When the winding drum is cylindrical the rope round and not 
 winding on itself, determine the circumference of the drum, the 
 number of coils or rope, then the amount of rope between the 
 two marks can be roughly calculated. When the rope winds on 
 itself during part of the hoist, correction must be made for the 
 increased diameter due to the rope. When the drum is conical, 
 measure the diameters at each end of the surface on which the 
 rope is wound, determine the number of coils of rope wound 
 during hoisting the length of rope can then be roughly esti- 
 mated. When the spiral drum or differential drum is used it is 
 necessary to know the equation of the curve of the drum, the 
 number of grooves per foot of face of drum and the number of 
 coils of rope wound. When flat rope is used, the thickness of 
 rope, diameter of reel or reel and rope when the skip is at the 
 bottom, diameter of reel and rope when the skip is at the top 
 should be determined. Then either algebra or calculus may 
 be employed to determine the length of rope. 
 
 c. "A steel wire is unwound from a reel on the surface and 
 passed over a pulley, dropping down into the shaft and held 
 taut by a weight at the end. There is a horizontal scale over 
 which the wire passes. The measurement is begun by lowering 
 the weight a short distance and placing a mark on the wire at a 
 point which is at the height of the point from which the depth 
 is to be measured. At the same time a slight mark is made in 
 the wire opposite the zero point of the scale. The wire is then 
 unwound until this mark moves to a point of graduation when 
 this distance of travel is measured on the scale and recorded. 
 Then another mark is put on the wire at the zero point and 
 another part is measured, and thus the measurement continues 
 by segments until the weight has nearly reached the bottom 
 of the shaft. Then a level line from an instrument (under- 
 ground) will determine a point on the side of the shaft at the 
 height of the first mark made on the wire. Then 'the last portion 
 of the wire that was unwound is measured on the scale and the 
 total depth is equal to the sum of all the parts measured on the 
 scale. The depth may also be measured when the reel is wound 
 up and the two results compared."* 
 
 *Nugent's Plane Surveying, p. 356.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 25 
 
 d. The depth of shaft may be measured directly. by means 
 of a tape. A nail is driven in the collar of the shaft, the eleva- 
 tion of which nail is known and from which nail is suspended the 
 tape. Then a man with the reel on top of the cage, unwinds 
 the tape as the cage is lowered till the end of the tape is reached. 
 Then he drives another nail, ascends to surface, unhooks the 
 tape and proceeds to the last nail set ; again from that point he 
 proceeds as before until the reaches the bottom. 
 
 e. An instrument equipped with top or side telescope may 
 be set up over the shaft and the heighth of instrument being 
 known, the telescope is depressed until the vertical circle shows 
 that the telescope is vertical. A point on the bottom is then 
 established directly under the instrument, but distant from the 
 center the distance between telescopes. In the line of the 
 telescope another point as far as possible from the first point 
 is established on the bottom and the vertical angle to this is 
 read. Both points on the bottom should be at the same eleva- 
 tion. The distance between these points can be measured. We 
 have then a right triangle, which can easily be solved for the 
 long side the depth of shaft. In order to check this, several 
 lines may be established in the same way and the depth calcu- 
 lated. 
 
 Knowing the elevation of the collar and the depth of shaft 
 the elevation of the bottom is determined and proper bench 
 marks are established. 
 
 f. To determine the elevation of the bottom of an inclined 
 or crooked shaft, it is generally advisable to run a traverse with 
 the top or side telescope from a known bench mark on the 
 surface. The depth of shaft can then be readily computed. 
 
 To carry the meredian down an inclined shaft or slope it 
 becomes necessary to observe (a) the horizontal angle or azimuth 
 (b) the vertical angle, (c) the distance, (d) the height of instru- 
 ment and (d) the height of the point sighted. For highly in- 
 clined openings it becomes necessary to use an auxiliary tele- 
 scope because of the interference of the main telescope with the 
 plate. Eccentric bearings may be used but most engineers 
 prefer the auxiliary telescope. Such telescopes must be ad- 
 justed so that by easy calculations the proper line may be found. 
 The top telescope is mounted so that when the main telescope 
 is horizontal, it is also horizontal and with the vertical wire in 
 the same plane with the vertical wire of the main telescope. The 
 horizontal wire of the top telescope should be so adjusted when 
 sighted say at a rod two hundred feet from the instrument, the 
 main telescope being horizontal, the difference in readings on 
 the rod corresponds to the vertical distance between telescopes.
 
 26 A STUDY OF MtNE SURVEYING METHODS 
 
 When the side telescope is used, horizontal wires of the 
 main and of the auxiliary telescope should be in the same plane 
 and when the instrument is sighted at a vertical plane surface 
 about two hundred feet distance instrument, the distance be- 
 tween points in the line of sight of the main telescope and the 
 side telescope should correspond to the horizontal distance 
 between telescopes. 
 
 Distances may be measured from the instrument or the 
 station established to either the point of sight or the next 
 station. Most engineers prefer to measure from the axis of 
 the main telescope to the point sighted. It becomes necessary 
 then to make various readings. Notes are often kept in the 
 following form: 
 
 Az. | Mag. Bear. | V. A. M. D. | H. I. | H. Ft. 
 
 An accompanying figure shows for the top telescope the 
 various angles and distances, except azimuth, which should be 
 noted. The distance between telescopes should be a constant. 
 Numerous Greek letters have been eliminated, in order that the 
 difficulties, which are numerous enough for the average student, 
 be not multiplied. The object has been to make the student 
 think in terms of actual observations rather than in abstract let- 
 ters. 
 
 The student should note that in the use of the side tele- 
 scope when the vertical angle is 90, no point above or below 
 the instrument can be sighted if it lies within the right cylinder 
 generated by turning the instrument on the horizontal plate. 
 This cylinder will have a radius equal to the distance between 
 telescopes. Under the same conditions a top telescope will 
 also generate a similar right cylinder but this 'cylinder does not 
 mark the limit of sight of the top telescope. Points directly 
 under the center of the instrument are visible up to a certain 
 limit which is determined by the ratio between the distance 
 between the telescopes, the diameter of horizontal plates and 
 the height of standards. Assume a point directly under the 
 center of the instrument ; this is not visible through the side 
 telescope but may be through the top telescope if the vertical 
 angle is not much over 90. An infinite number of horizontal 
 angles but only one vertical angle may be read for such a point 
 as it is the apex of a right cone, the center of whose base is the 
 center of the instrument. Any point above the plane of the 
 plate of an instrument is visible through the top telescope. 
 
 Plumb lines and wires may be used to carry a line from the 
 surface underground through an inclined shaft. When the 
 shaft is sunk on several dips the problem requires considerable 
 care. When the line of the shaft is known approximately, a
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 27 
 
 wire is stretched from the surface to a point well down the shaft. 
 The bearing of the wire is established by two bobs hung so that 
 the cords just touch the wire on the same side. Two bobs are 
 hung in the same manner underground. When the shaft is on a 
 uniform dip, the wire may be stretched taut ; when the dip dimin- 
 ishes the wire may be hung to clear the sag in the shaft. Plumb 
 bobs are hung on the line in the same. way. Having established 
 two points underground, the wire may be taken down the shaft 
 and hung in the line of the two stations and two more establish- 
 ed further down. Great care must be taken that bobs are always 
 hung on the same side of the wire and that all points are proper- 
 ly aligned. 
 
 When two or more inclined shafts are connected under- 
 ground surveys should be made if possible connecting survey 
 points established at the various levels. When there is but one 
 opening, in carrying the meredian into the mine, great care 
 should characterize the work. All surveying should be care- 
 fully done but greater precision is essential to shaft work, espe- 
 cially when but one line can be run, because all subsequent 
 work depends upon the accuracy in location of the shaft stations. 
 
 Vertical shafts. When there is but one vertical shaft there 
 is nothing to check the work. 
 
 a. When the shaft is not very deep or wet the transit 
 equipped with Auxiliary telescope, may be used. The instrument 
 is set up at the collar of the shaft, back sight is taken on a 
 known point and two points in the line of the instrument are 
 established at the bottom of the shaft, as far apart as possible 
 and both visible from the tarnsit. The azimuth of the line un- 
 derground can be readily calculated when all the distances are 
 measured. This method is used in some of the deep level shafts 
 of the Rand. 
 
 b. For deep and wet shafts it is advisable to hang wires 
 from the slurface. When there are two shafts, but one wire is 
 necessary to each shaft. Underground and surfaces traverses 
 are run to connect the wires which should be suspended at the 
 same time. The azimuth of the plane through the two wires 
 can thus be determined. When there is but one opening two 
 wires should be hung from the surface in a line the azimuth of 
 which is known. Copper or steel wire may be used ; copper is 
 generally preferred for shallow shafts. Hang an 8 pound bob 
 from a No. 20 copper wire. These wires should be as far apart 
 as possible, should hang free, should not interfere with hoist- 
 ing and should be so located that the transit can be set up in 
 line with them underground. The wires should be lowered from 
 the surface, a light bob being attached to the wire in order to 
 keep it from catching on timbers, etc. When the wire extends
 
 2$ A STUDY OF MINE SURVEYING METHODS 
 
 to the bottom, it should be drawn up so that it will clear the 
 bottom even though it does stretch a little. It is generally ad- 
 visable to lower the wires one at a time and to draw the first 
 wire taut in the same corner from which it is suspended at the 
 surface in order that the second wire may not be. entangled 
 withjtr In plumbing the Tamarack shafts 4,250 feet deep, No. 24 
 piano wire was used. This was lowered by means of a small 
 two cylinder hoist operated by compressed air. The lowering 
 weights consisted of two balloons or frames, ten feet long and 
 two and a half feet in diameter at center tapering to a point at 
 each end. These were made of slats and weighed twenty pounds. 
 A lantern was hung in the center of each so that its progress 
 down the shaft might be observed. It took half an hour to- reach 
 the bottom. Eight pound bobs were then attached and the lines 
 brought so far from the center of the shaft as possible. When 
 the wires were in place fifty pound cast iron bobs were substi- 
 tuted for the eight pound ones, when the wires immediately 
 stretched fifteen feet. They were then cut to the proper length 
 and the bobs immersed in pails of engine oil ; this resulted in 
 the shortening of the wires twenty-five inches due to the buoyant 
 effect of the oil on the weights. One of the members of the 
 party should inspect the wires to see that they are hanging free. 
 It is always advisable to see that no ventilating currents cause a 
 deflection of the wires. Water, oil or molasses may be placed in 
 the vessel in which the bobs hang. 
 
 The distance between the wires and the azimuth of the line 
 through them should be carefully determined. Then set up the 
 tripod underground as nearly as possible in line with the wires 
 and by means of the shifting head place the transit in the line 
 of the wires. The known line on the surface is thus projected 
 underground. Establish a point over the instrument and another 
 point in the line of, the wires, at a good distance. Measure the 
 distance between the wires and distances from the instrument to 
 the wires and to the established point. 
 
 When the compartment of the shaft is. small it is advisable 
 to hang more than two wires. When four are hung, their posi- 
 tion should be determined on the surface with regard to some 
 known line. Two points should be established underground, 
 from each of which the other can be seen and also all the wires. 
 Set up at both points, read the angles to the wires and the 
 other point and measure the distances. Calculate the azimuth 
 of the line through the two established points. 
 
 Plumbing shafts requires considerable time and often in 
 order to make the interference with mining operations as brief 
 as possible, engineers do not wait for the bobs to come to rest 
 but bisect the arc of vibration. This may be done by tracing on
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 29 
 
 a sheet of paper the elliptical path of the bob as it swings. The 
 center of the ellipse can then be taken as the point of sight, or 
 the extereme points in the arc of vibration may be marked on a 
 sheet of paper placed on a heavy board, the line joining these 
 points is bisected and the middle point taken for the sight. Var- 
 ious other methods may be used in carrying the meridian down 
 the shaft. The co-called T square method* has been successfully 
 use on the Comstock lode. 
 
 UNDERGROUND TRAVERSING. 
 
 By a traverse is meant a series of consecutive courses 
 whose lengths and bearings, or azimuths, are determined. A 
 traverse is then a system of connected lines, the second starting 
 from the first, the third from the end of the second and so on. 
 A transit is said to be "oriented" when it is set up with the hor- 
 izontal circle in such a position that if the vernier is made to 
 read zero the line of sight will be parallel to the meridan. When 
 carrying on an extended survey it it most convenient to carry 
 angles by the continuous azimuth. Many engineers prefer to 
 read angles between lines of the traverse, always turning either 
 to the right or left. These reading can be easily checked by 
 repeating the angles. Having established the azimuth of a line 
 underground, the meridian can be carried to any part of the 
 excavation and by accurate measurements the position of any 
 point determined with regard to any other, either underground 
 or on the surface. For accurate work vertical angles should 
 always be read and measurements taken from the axis of the 
 instrument to the point of sight, the height of instrument, 
 height of point and measurements to show the distances of the 
 stations from the walls and distances to any irregularities not 
 sufficient to deflect the traverse. When a line is being extended 
 in order to determine the proper direction to drive an opening 
 to connect with another, very few measurements save those es- 
 sential to the traverse are taken. In mapping a mine all exca- 
 tions must be noted and measured so that they may appear 
 properly on the map. 
 
 The duties of the various members of the party have already 
 been noted. 
 
 The cross wires may be illuminated by (a) a reflector, an 
 elliptical silvered plate inclined at an an angle of 45 with the 
 ring which carries it, and by means of which it is fitted to the 
 object end of the telescope ; (b) by a half cylinder of white 
 cardboard fastened to the telescope with an elastic band, and 
 light reflected from it to the cross hairs ; (c) by use of a sheet 
 *Mines and Minerals XIX, 242.
 
 jo A STUDY OF MINE SURVEYING METHODS 
 
 of white paper rolled into a cone truncated, placed with the 
 large end over the object glass, a circular hole cut in the middle 
 of the cone and a candle held opposite the hole. 
 
 The transitman sets up under a known point ; the back- 
 sightman illuminates the point under a known station. The 
 transitman clamps the vernier on the known azimuth of the 
 line determined by his instrument and the backsight ; plunges the 
 telescope and sets on the backsight and clamps the lower plate. 
 (Some engineers prefer to set the vrnier at 180 less than the 
 reading for the last foresight on the main traverse and back- 
 sight without plunging the telescope.) Then he plunges, sights 
 on the new point established in the meantime by the foresight, 
 clamps the lower plate and reads the azimuth of the line through 
 the point of transit and the new point. For accurate work he 
 should repeat the angle. Then the instrument man reads the 
 vertical angle and measures the height of instrument, while the 
 foresightman measures the height of point and together with 
 the instrument man or backsightman measures from the axis 
 of the instrument to the point sighted. The distance is known 
 as the "measured distance" or "slope distance." 
 
 The three tripod method of traversing has been used some- 
 what but is not considered very practical in that it requires 
 three tripods and requires that the party shall contain a man, 
 in addition to the transitman, who can set up an instrument so 
 that it can be used for often a considerable lenght of time. It 
 is totally impracticable for traversing along roadways in which 
 traffic frequently interrupts the surveying party. The equip- 
 ment for this work comprises an ordinary transit, three exten- 
 sion tipods so constructed that the transit can be undamped 
 and removed, leaving the leveling screws on the tripod, and two 
 plummet lamps which may be set and clamped upon the tripod 
 when the transit is removed. These lamps carry spirit levels so 
 that they can be leveled. The steps in the operation are these: 
 Suppose the transit to be set up under a known point ; a back- 
 sight is given by plumb bob ; the elevation of the station being 
 known ; the height of instrument is determined. The foresight- 
 man sets .up under the next point, centering and leveling as with 
 the transit ; having properly set up, the tripod being set very 
 firmly, the lamp is lighted and the foresight given. When the 
 point of sight on the light is the same height above the plate 
 as the telescope, the height of instrument need be taken only by 
 the foresightman. Having measured distances and read the 
 angles the transitman takes the transit off the tripods, takes the 
 third tripod from the backsightman, and carries tripod and tran- 
 sit to foresight. The foresightman removes his plummet from 
 the tripod in place, places it upon the tripod brought up by the
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 31 
 
 transitman and goes ahead to establish the next station. The 
 transitman simply sets his instrument upon the plate already 
 centered and leveled and is ready to backsight. The transitman 
 does not have to bother setting up, but it generally pays to have 
 him check the set up before making any sights ; so the real 
 purpose of the three tripods is not gained. 
 
 In working with the top and the side telescopes, or with 
 angles above 60 trouble is apt to occur from the increased and 
 magnified effects of personal and instrumental errors. These 
 errors may be divided into classes (a) variable errors, and (b) 
 constant errors. 
 
 a. Variable errors. I. Centering the instrument. A 
 sight of 50 feet with a vertical angle of 85 gives a horizontal 
 distance of 4.35 feet. In a circle of that radius an arc of .0013 
 feet subtends an angle of one minute, which means that a dis- 
 placement of .0013 feet in position of the instrument bob would 
 give an error of that amount 
 
 II. Leveling the instrument. If the plate is one minute 
 from the horizontal an error of eleven minutes in azimuth may 
 occur with the vertical angle of 85 
 
 b. Constant errors may be due to inclination of the stand- 
 ards, errors in collimation and the eccentricity of the telescope 
 axis. 
 
 The work should be carried on and the notes so kept that 
 any other surveyor can come in and take up the work at any 
 
 " c 
 
 SURVEYING THE MINE. 
 
 - The survey of the mine as a whole has for its object the 
 production of a map to show essentially the underground work- 
 ings For flat veins, seams or beds, a horizontal plan is generally 
 the only map made. However for highly inclined veins in order 
 that all features of the work may be readily observed it is not 
 uncommon to make three or four sheets, a horizontal projec- 
 tion a vertical projection, a vertical section, and a projection 
 of the vein itself. In common practice the survey of the mine 
 means nothing more than a determination of the amou 
 position of excavation. 
 
 To survey the mine properly it is essential that some gen- 
 eral plan be first laid out and that, so far as possible, tl 
 be closely followed. In traversing drifts, irregularities should 
 be noted so that if of importance they will appear on tl 
 all openings should be noted. 
 
 In surveving coal mines, the angle at which rooms are 
 turned off should be measured, the rooms properly located wit 
 re-ard to the entry, all dimensions carefully taken and all oper 
 
 ^: 4 <*-/. 
 
 As 2
 
 32 A STUDY IN MINE SURVEYING METHODS 
 
 ings correctly located. When openings are closed, gobbed or 
 bratticed they should appear so in the notebook. Even though 
 such features are not to be mapped, the surveyor should make 
 his book a record of actual conditions, in the mine when the 
 survey is made. 
 
 In surveying a longwall mine, it is necessary to show the 
 roads that are open and the working face. Points about 40 
 feet apart are located and the face is then drawn in the notebook. 
 The traverse may be carried along the face but this is gen- 
 erally very dangerous and points established are so near to the 
 working face that they will be blown out by blasting. 
 
 In surveying large stopes it is often impossible to use the 
 transit. Special methods must then be adapted. The various 
 types of clinometers and needles on cords have been successfully 
 used. Hand compasses or hand transits are then of great 
 assistance. A few hours' work with the Brunton will show its 
 applicability to this grade of work. The method of off-setting 
 with tapes is commonly used- in metalliferous mines. 
 
 There is considerable difference in the method of conduct- 
 ing a survey when one is in the regular employ of a company 
 and when one is doing only custom work. More permanent 
 stations should be established in the former case than in the 
 latter. 
 
 The field book should be a regular and accurate record of 
 the work of the surveying party irrespective of the continuity 
 of the work, or several books should be used so that a con- 
 tinuous record may be kept in one book of the work in one 
 mine or one section of the mine. Notes should be so well 
 taken that they can be worked up "cold," that is, any time after 
 the survey is made by any one. It is advisable to keep the map 
 work up close to field work. Very often surveys must be made 
 at regular intervals. Where such is not the case, and the sur- 
 veying party does the mapping, each day's work should be com- 
 pleted before another is begun. That is, all calculations of 
 traverse should be made the same day the field work is done. 
 This often works hardship to the instrument man, but after sys- 
 tematizing his work he will find it easy and will want to do it. 
 Mapping can be reserved for odd days. 
 
 Side notes can be kept best by using the right hand page 
 of the field book for sketches, the left hand for angles, dis- 
 tances, etc. Sketching and all notes should begin at the bottom 
 of the page and follow up the page. The center line of the page 
 should be taken as the line of traverse. Sketch to a convenient 
 scale, and do not crowd the notes. Always take enough meas- 
 urements and sketch carefully. Some engineers do not attempt 
 to show to scale distances from the traverse, but put in dimen- 
 sions so that the notes can be easily interpreted.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING jj> 
 
 GEOGNOSY. 
 
 Preliminary to beginning underground operations it is 
 often necessary that the location and extent of the deposit to 
 be mined should be determined. When there is an outcrop, this 
 can generally be more easily accomplished than when there is 
 no surface indication. 
 
 Stratified Deposits. Flat seams of coal are often so cut by 
 streams that an outcrop may be traced for many miles. A tra- 
 verse may then be run along the outcrop to determine the 
 boundaries of the coal. Often the outcrop of an overlying 
 measure is taken as an indication of coal and it is then common 
 to run a so-called "crop line" along the outcrop. When the 
 measures are intersected by streams large tracts of coal are 
 often platted in this way. When the tract is not completely 
 severed from the adjoining area, it becomes necessary to put 
 down bore-holes. These will show the depth of the coal horizon 
 and together with the crop line will serve to locate and bound 
 the tract. When the measures are inclined and outcrop in a 
 flat country,* the outcrop should be traversed and bore-holes 
 should be put down to intersect the productive measures. The 
 depth of the holes and their position with regard to the outcrop 
 being known, the productive area or acreage can be platted. 
 
 When the measures are overturned or vertical at the out- 
 crop and then slope off to horizontal it becomes more difficult 
 to estimate acreage and, finally, the tonnage. Faults frequently 
 displace measures so that calculations are unreliable. The fault 
 plane, throw, etc., must be positively established before any esti- 
 mates or plats can be made. In many districts in the central 
 states, the coal measures are horizontal and covered with glacial 
 debris. The coal has at places been completely eroded, at oth- 
 ers is covered with but a few feet of rock and at others by several 
 hundred. The continuity of the coal can be determined only by 
 very numerous drill holes, as many as six hundred to the section 
 being common practice. 
 
 Outcropping veins should be traversed, their strike and dip 
 determined, and their intersections and any disturbing fault 
 planes carefully located. When there is no outcrop, drill holes 
 may be put down to intersect veins. Knowing the location, 
 depth and angle of these holes to intersect the vein, the position 
 of the vein is determined and the mineral acreage may be ap- 
 proximately determined. 
 
 Masses or lenses' of ore appearing on the surface should be 
 surveyed and drill holes located at regular intervals. The holes 
 being vertical, their depth and location being known and platted
 
 34 A STUDY OF MINE SURVEYING- METHODS 
 
 the volume in the mass may be calculated and the tonnage esti- 
 mated. When masses or lenses do not outcrop ; drill holes should 
 be put down to intersect the mineral. The depth at which the 
 drill enters and leaves the ore body being noted for each hole 
 and each hole being properly located on a contoured map, the 
 volume of the mass can be determined. 
 
 Alluvial deposits should be carefully mapped and drill holes 
 so located and mapped that the volume of material as well as the 
 extent and depth of rich strata may be determined. 
 
 The importance of surveying in the work preliminary to 
 mining operations can be readily seen. No legitimate mining 
 enterprise is attempted without a fair knowledge of the extent 
 of the body upon which operations are to be carried on. A 
 complete contoured map is always of great advantage to the 
 engineer who is locating a deposit. 
 
 DRILL HOLES. 
 
 It is frequently assumed that bore holes are straight ; that 
 is, if started vertical, they continue so, or if started on a known 
 angle they continue on that angle. This is seldom the case, for 
 the holes are deflected from their course. This is more likely 
 to occur in vertical holes with the diamond drill than with the 
 percussion drill. However with the percussion drill when the 
 rods are not very long, the rod tends to work to one side and 
 may soon be deflected from the vertical. The falling weight, 
 however, has a tendency to straighten the hole. When the 
 diamond drill is used for an inclined hole it is almost impossible 
 to maintain the desired angle because the drill rods are of a 
 smaller diameter than the bit and will lie against the bottom or 
 side of the hole and by this deflection the face of the bit is in- 
 clined from the proper bearing. In order to ascertain the course 
 that has been taken by a bore hole it is necessary to make a 
 survey just as it is necessary to survey a tunnel. Many diffi- 
 culties must be overcome, and to this end many ingenious de- 
 vices have been adapted. Nolten's instrument consists essential- 
 ly of a glass cup in which is placed hydrofluoric acid. When 
 the cup is placed in a bore hole in an inclined position, the acid 
 will attack that part of the glass below the level of the acid. 
 A line will then mark the angle of inclination of the glass cup. 
 While the acid is being lowered into the hole the acid will shake 
 about and will leave no clear mark upo^i the glass ; when it has 
 reached the. required depth, if it is allowed to remain unmoved 
 for half an hour, the acid will etch a permanent record of the 
 inclination of the glass and also of the tube in which it is fixed. 
 In order to record the direction in which the hole is proceeding, 
 in case it is not perfectly vertical, another instrument is com-
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING jj 
 
 bined with this one and fixed in the same tube. This instru- 
 ment consists of a compass needle free to revolve in a horizontal 
 plane on a vertical pivot, and of a watch which can be set to 
 operate a lever, so that the needle can be clamped at the exact 
 time at which the watch is set. When lowered into the hole, 
 the needle after being allowed to come to rest is clamped, and 
 will show the direction of inclination because the compass is fas- 
 tened to the tube. 
 
 Ordinary gelatine is easily melted when immersed in hot 
 water and solidifies again at 70 F. When melted it takes sev- 
 eral hours to stiffen. A clinometer and compass placed in a 
 tube containing melted gelatine and lowered into a bore hole 
 will show the direction and inclination if the gelatine is allowed 
 to cool. 
 
 Various other devices may be used. It has been found that 
 in a depth of 370 feet a bore hole had deviated 37.5 feet in a 
 horizontal direction from the vertical. It cannot be assumed, 
 then, that bore holes are vertical when deep deposits are being 
 prospected. In order to block out the ore body, holes must be 
 platted in their true position. Frequently a diamond drill is set 
 up underground and holes at various angles are used to explore 
 the adjacent ground. Also in driving drifts towards abandoned 
 mines it is necessary to carry holes ahead and to the sides of 
 the drifts in order to avoid breaking into bodies of water or gas. 
 
 LOCATING OPENINGS AND MINE PLANT. 
 
 In locating and blocking out ore bodies various openings 
 are necessary. Samples must be taken in order to determine 
 the quality of the ore. Openings provide the means for getting 
 such samples and for determining the quantity of material that 
 can be mined. Such openings must be carefully located. By 
 means of bore holes samples can be obtained from ore bodies 
 at considerable depth. Shafts, tunnels and drifts better serve 
 this purpose but the cost being much greater these generally 
 give way to the bore holes for systematic and extended explor- 
 ation. 
 
 The extent and depth of the ore body being determined by 
 careful surveys of the exploratory openings, the sites for per- 
 manent openings and buildings are surveyed. A contoured map 
 is always of great service in laying out the mine plant. Mine 
 openings should be so placed that surface water will not run 
 into the mine that a very high building will not be necessary 
 to secure fall enough to run the product of the mine to the mill 
 or into railroad cars, and that there is sufficient clump room. 
 When upon the side of a mountain, openings must be placed 
 out of the paths of rock and snow slides. The surface plant
 
 j6 A STUDY OF MINE SURVEYING METHODS 
 
 being located, the underground workings may be laid out. 
 When a flat coal seam is to be mined, large companies generally 
 make a plan showing how openings are to be driven and how 
 working places are to be located. When seams dip consider- 
 ably, it becomes necessary to establish roadways on grade. Gen- 
 erally these can be laid out on paper. When the conditions af- 
 fecting the method of working are known, ore bodies may be 
 blocked out similarly. That is, if we krtow a vein is regular 
 and dips at a certain angle, levels and stopes may be platted 
 and workings made to conform with this plan. Such plans 
 are, of course, ideals and may not be attained, but it is always 
 well to have in mind* such ideals and then endeavor to carry 
 out the system planned. If the tract has been properly ex- 
 plored without the use of drifts, tunnels and shafts, openings 
 may be so located that with a minimum amount of dead work 
 a maximum tonnage may be produced at a low operating ex- 
 pense. Faults, irregularities, old stream channels, poor coal, 
 poor roof and old workings may be avoided. Some companies 
 in Pennsylvania require all openings to be driven straight 
 and rooms to be driven at a given angle irrespective of local 
 conditions. In laying out the mine workings on paper, proper 
 pillars should be left for shafts, roadways, boundaries and 
 buildings. Failure to determine the position of buildings on 
 the surface \vith regard to mine openings has often been re- 
 sponsible for disasters. Witness the cave in at the Negaunee 
 mine which incapacitated the hoists for two shafts, thus pre- 
 venting the immediate removal of debris in order to release 
 the miners. 
 
 The mine surveyor then is largely responsible for the laying 
 out of the mine and arrangement of the mine plant. 
 
 SHAFT SINKING. 
 
 In sinking large shafts the surveyor generally plays an 
 important part. The shaft must be kept vertical or upon a 
 given pitch. When the shaft is sunk on the lode regardless of 
 change of dip, it becomes necessary to place frequent rollers 
 or pulleys to carry the hoisting rope. Many companies today 
 in sinking large shafts decide dpon a given angle for the 
 shaft and sink regardless of walls. The surveyor must then 
 not only keep the work progressing in the proper direction 
 but establish points by which the proper vertical angle may be 
 maintained. 
 
 Record of the depth must be given regularly and points 
 located so that the plats or stations may be cut at the proper 
 intervals. When sinking has progressed to a lower level and 
 the plat has been cut the timbermen require the surveyor to
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 37 
 
 locate for them by elevation the sleepers to carry the skip 
 rails. In order to do this the surveyor proceeds as follows: 
 The transit is set up over the rail at a known point, the 
 shortest distance is measured from the axis of the telescope, 
 when the angle of the shaft is large the top telescope, to the 
 sleeper; at about 100 feet back a leveling rod with the target 
 set at the distance just measured at the instrument is placed 
 on the sleeper and held at right angles to the sleeper ; the tele- 
 scope is then sighted on the target and the vertical angle read ; 
 this should be the established shaft angle. If it 'checks pro- 
 perly, the rod reading is recorded and the rodman goes down 
 the shaft to the point at which marks for setting sleepers are 
 desired. He places his rod along the stulls or shaft timbers 
 so that the rod makes a right angle with the established line 
 of the shaft. The transitman has the rodman place the target, 
 clamped, as already noted, in the line of the telescope when 
 set at the proper vertical angle. The zero of the rod then 
 determines the proper point for the top line of the sleeper. 
 
 Along shafts which are not straight as previously noted, 
 pulleys, sheaves or rollers must be properly placed. It fre- 
 quently falls to the lot of the surveyor to determine the proper 
 points for such rollers. The proper line for the rope must 
 then be determined if possible analytically ; generally, how- 
 ever, a few experiments will show where the pulley is needed. 
 
 TUNNELLING. 
 
 In driving a tunnel for prospecting purposes or for trans- 
 portation, the surveyor must give the direction, distance and 
 grade. The direction may be established by three points placed 
 on lines. One of these points should be a permanent station 
 and not less than thirty feet from the breast, the other two 
 about six feet apart and one not less than ten feet from the 
 breast. By hanging plumb lines from these stations the work- 
 men can properly align their work. Unless precautions are 
 takn the walls will not be driven straight. The walls of the 
 tunnel should be equidistant from the established line, or some 
 given distance. Timbers should be set on line. 
 
 "In very long tunnels excavated under high mountains 
 more elaborate methods have to be adopted for locating the 
 center line. The theodolites employed must be of large size: 
 in ranging the center line of the St. Gothard tunnel, the theo- 
 dolite used had an object glass eight inches in diameter. Instead 
 of the ordinary mounting a masonry pedestal with a perfectly 
 level top is employed to support the instrument during the obser- 
 vations. The location is made by means of triangulation. The 
 various .operations must be performed with the greatest ac-
 
 jS A STUDY OF MINE SURVEYING METHODS 
 
 curacy, and repeated several times in such a way as to reduce 
 the errors to a minimum, since the final meeting of the head- 
 ings depends upon their elimination." 
 
 "The triangulation was compensated according to the 
 method of least squares. The probable error in the fixed direc- 
 tion was calculated to be 0.8" of arc. From this it was assumed 
 that the probable deviation from the true center would be about 
 two inches at the middle of the tunnel, but when the headings 
 finally met this deviation was found to reach eleven inches."* 
 
 The cross section of a large tunnel** may be taken by a 
 method of polar co-ordinates. A light brass protractor in a 
 vertical plane is mounted on a tripod ; to this protractor is 
 secured a light measuring rod, graduated to tenths, which 
 slides upon a rest on the face of the protractor. Points in the 
 cross section are measured by setting the plane of the pro- 
 tractor at right angles to the axis of the tunnel and then slid- 
 ing the rod out until it touches the wall. Read the length on 
 the rod and record the angle, and so on for any number of 
 points on the circumference of the tunnel section. 
 
 In order to properly drain the tunnel and that a uniform 
 grade in favor of loaded cars may be maintained, the surveyor 
 should regularly establish grade points for the foreman. 
 
 MINE WORKINGS. 
 
 In well planned mines, the surveyor must almost daily 
 establish points for the shift boss or foreman in order that 
 rooms, stopes, raises or breakthroughs may be driven as 
 planned. In some states breakthroughs must be driven at a 
 minimum distance apart. The surveyor must keep the mint 
 so surveyed that he can quickly establish such points. It is 
 
 good practice to set points for the center line of openings, 
 enerally it is necessary to give such points at first only tem- 
 porarily as stations established so near a working face will be 
 disturbed ; after the work has proceeded sufficiently permanent 
 points may be put in. 
 
 pji-Jp CURVES AND CONNECTIONS. 
 
 It is often necessary to drive a curved entry in a mine in 
 which rope or motor haulage is used and especially where cars 
 must travel rapidly from the side entries into th % e main entry. 
 These curves are often quite sharp and are described with 
 regard to their radius rather than to curvature in degrees. 
 The method of laying out these curves differs from railroad 
 
 *Prelinis Tunneling, p. 10. **A. S. C. E. XXIII, 17.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 39 
 
 practice only in that all points cannot be established at one 
 time. Points should be set daily by which the miners can 
 drive. Points should not be more than ten feet apart. 
 
 One of the most important phases of mine surveying and 
 probably what requires most care is a survey for openings to 
 connect two given or assumed points. Numerous problems 
 will arise upon which will depend the reputation of the sur- 
 veyor. The principal precautions that should be taken are (a) 
 the adjustment of the instruments, (b) the complete survey 
 should be made by one squad, (c) all stations should be per- 
 manent if possible, (d) all measurements and readings should 
 be checked. The surveyor may be called upon to establish the 
 line for 
 
 (a) a railroad tunnel driven on grade from both ends, 
 
 (b) a railroad tunnel driven from both ends and from 
 shafts sunk along the line of the tunnel, 
 
 (c) a mining tunnel to connect with a shaft 01 vice versa, 
 
 (d) a drill hole to intersect mine workings, 
 
 (e) a cross cut to connect workings on adjacent veins, 
 
 (f) a raise to connect a given point on a level and a shaft 
 or another level, and 
 
 (g) air courses to connect working places. 
 
 OPENINGS TO INTERSECT VEINS. 
 
 In many of the important mining districts engineers have 
 been called upon to solve various problems which require the 
 application of that division of geometry generally known as 
 descriptive geometry. Certain assumptions must be made in 
 all cases but the results obtained prove of considerable value 
 in that no greater error can occur when conditions as noted 
 continue, and the results of such solutions are generally better 
 than guesses. 
 
 In the Cripple Creek, San Juan and Clear Creek districts, 
 shoots and zones of ore occur adjacent to the intersections of 
 veins. Practical miners say that "invariably" will ore be found 
 at these "junctions" and that it is always advisable to drive to 
 such points. Many openings are put down in quest of such 
 intersections when it is supposed that they exist and many feet 
 of work show that often the miner has "stayed with the ore" 
 when he might have taken a short cut and saved much money 
 and labor. 
 
 The following assumptions should be made in working out 
 problem? graphically: (a) The surface is assumed to be a hori- 
 zontal plane, (b) Veins are planes of uniform dip; intersec- 
 tions of veins are straight lines; thickness of veins- is not to 
 be considered, (c) Shafts on veins will be straight, (d) Ex-
 
 40 A STUDY OF MINE SURVEYING METHODS 
 
 cept when the grade is specified, tunnels are horizontal, also 
 drifts, (e) Dimensions of shafts and tunnels should not be 
 considered, that is, openings are considered to be straight lines 
 (f) All inclined shafts to be the shortest possible. In the 
 solution of problems in practice, the scale used should be such 
 that the errors of platting do not materially change the results. 
 
 It is very difficult; in fact almost impossible except in 
 stratified measures, to solve problems of faulting. In all cases 
 certain assumptions must be made. If actual conditions are 
 not known and the continuity of the vein or seam is not known, 
 any solution cannot be accepted. In all cases results of such 
 solutions can be given as only probable or possible. Change 
 of dip or strike, faults or other irregularities may easily render 
 such solutions valueless. 
 
 Many of these problems the engineer can solve analytic- 
 ally and can check the graphical method. Having determined 
 the proper solution for any problem similar to those given the 
 surveyor has then only to establish points and from time to 
 time check up the alignment of the opening driven to make 
 the connection. 
 
 GEOLOGICAL IRREGULARITIES. 
 
 As previously noted all irregularities should be noted and 
 mapped. Fault planes, horses, rolls, water courses, etc., if 
 properly mapped in one level and drift may be anticipated in 
 driving new openings. Intersections of veins may be opened 
 up in lower levels without undue loss of time if they have been 
 carefully located in the upper workings. The dip and strike of 
 veins should always be noted even though there be not any 
 values in sight. In surveying tunnels all veins that are cut 
 should be mapped and, if possible, identified and described. 
 Failure to note all the veins cut has in many cases resulted in 
 much useless dead work. The character of walls and roof 
 should be noted, as well as the thickness of the vein. 
 
 DRAINAGE. 
 
 The surveyor is frequently called upon to establish a drain- 
 age system for a mine. In flat seams, he must then, if he has 
 not already done so, run a line of levels and determine the 
 proper points at which to establish small sumps from which 
 the mine water shall be conducted to the main sump. Some- 
 times it is possible to drain all the water into the old workings. 
 A complete map of old workings is necessary in order that 
 the volume of water that can be stored may be determined.
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING ji 
 
 Dams should then be placed where they may have good pillars 
 to hold them in place. Several of the large coal companies 
 carry all water in ditches in the back entries. Some of the 
 Michigan copper companies handle all the mine water through 
 one shaft. This necessitates that there be an opening con- 
 necting the mines so that water can run freely from any point 
 to the drainage shaft. Recently at Cripple Creek a tunnel has 
 been driven in order to drain a number of mines. This tunnel 
 was driven on line and grade to tap flooded workings. There 
 were three shafts on the line of the tunnel and in all, six points 
 of attack. The importance of an accurate survey can be readily 
 seen. 
 
 Impervious strata should be noted in drilling in order that 
 the system of mining may be properly adapted to conditions. 
 This is also important in locating sumps. The water level of 
 a district or mine should be determined and mapped and this 
 can best be accomplished only when complete records are kept 
 of all surveys and conditions at the time of survey. 
 
 When mine openings are driven through old stream 
 channels, as in the coal fields of some of the central states, it 
 is at times possible to discharge the mine water into the old 
 channels. However during the wet season of the year these 
 channels become filled with water and flood the mine. It is 
 generally advisable to line the openings so that water cannot 
 pass through. 
 
 HAULAGE. 
 
 Important road ways should be driven on grades which 
 
 are adapted to the system of haulage. The grade of tunnels 
 
 has already been spoken of. In mining in flat seams very fre- 
 
 quently rolls are encountered and these must be cut out. On 
 
 pitching seams roadways should be driven on grade. For rope 
 
 haulage the grade need not be regular, but if possible all irreg- 
 
 ularities should be eliminated. The surveyor is called upon to 
 
 ^._ establish points so that the work may progress in the proper . 
 
 /tj^if^cti^li, to put in curves where necessary and to establish ^ 
 
 /grade's.' 
 
 fo*- MAPPING. 
 
 '' /?<"'-/ ^'9 
 
 Two systems are used in mapping mines,' total' latitudes! 
 
 and departures, and by means of the protractor. Important 
 courses as in the main entries and shafts should always be * 
 platted by latitudes and departures and checked by the pro4 ^ 
 tractor. "Work with the protractor progresses much more\ 
 rapidly than with latitudes and departures but it is not very\ 
 accurate. 
 
 4
 
 42 A STUDY OF MINE SURVEYING METHODS 
 
 The size of sheet necessary for mapping the mine sur- 
 veyed and the probable extensions that can be economically 
 made from the main opening should be laid out in squares five 
 to ten inches on a side depending on the scale. 
 
 Coal mines are seldom made smaller than one inch to one 
 hundred feet. Metalliferous mines may be made to almost any 
 scale; generally a large map say one inch equal to thirty feet 
 is drawn to show stopes, rooms, etc., while another, one inch 
 equal to sixty, one hundred or two hundred feet, will show the 
 shafts and drifts. Several states require that map be made a 
 given scale. 
 
 For beds, horizontal or nearly so, a plan is sufficient. The 
 following quotations state briefly good practice for metalliferous 
 mines: "The survey is properly shown by at least three maps: 
 first, the plan or projection on a horizontal plane ; second, the 
 longitudinal section, generally the projection on a vertical plane 
 coinciding as near as may be with the general direction of the 
 levels; third, the transverse section or projection on a vertical 
 plane at right angles to the longitudinal one. The maps should 
 have a title giving the name of the mine and location by mining 
 district, county and state ; also there should appear the name 
 of the surveyor, date of survey, meridian used, and scale. The 
 map should be on cloth backed paper or tracing-cloth, and may 
 show on the plan the position, number, and elevation of the 
 permanent stations with the bearing and length of the lines 
 joining them or the coordinates of the stations, according to 
 the system used. The advisability of showing these data on 
 the map depends on the use that it to be made of them and 
 must be decided according to the nature of the case."* 
 
 The best practice today requires that all notes should be 
 copied from the field books and filed together with all cal- 
 culations so that at any time reference may be made to any 
 part of any survey. Calculations should be made by the use of 
 logarithms and so arranged that any one can check the work. 
 
 The record book may be ruled in the following form ex- 
 tending across one or two pages: 
 
 | 
 
 
 
 
 
 ^ 
 
 * 
 
 Q 
 
 Q 
 
 < 
 
 1 
 
 Latitude 
 
 o 
 
 o 
 Q 
 
 TOTAL 
 
 1 
 
 j 
 
 d 
 
 _!^_ 
 
 I 
 
 ^> 
 
 s 
 
 ~ 
 
 
 
 
 
 
 +|- 
 
 
 -f 
 
 
 
 Johnson's "Theory and Practice of Surveying."
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 43 
 
 Side notes should be preserved in the field book and may be 
 inked in in order to make them more legible. 
 
 Certain schemes once adopted should be continued. An 
 inspection of maps from various districts will show how varied 
 is the practice. One company will place the date of a survey 
 at the last station made by that survey on each shaft and 
 opening; another will use a letter or number to represent a 
 survey ; another will use colors on the maps, a distinguishing 
 color for each survey. Practice in showing worked out ground 
 is even more varied. The common methods are as follows: 
 (a) Printing on the map the phrase "worked out" over such 
 portions of the mine ; (b) by coloring the portions different from 
 the permanent openings and pillars ; (c) by hatching the bound- 
 aries of worked out portions ; (d) by dotting with inks. 
 
 Several of the largest companies photograph their maps 
 each year in order to keep a permanent and convenient record 
 of the progress. In such cases it is necessary to mark each 
 year's work so that it will show on the plat. 
 
 Frequently mine maps must be produced in court as evi- 
 idence. In all cases such maps should be so complete and 
 so carefully prepared that no questions can arise in regard to 
 the accuracy of the work of the engineer. Special maps and 
 diagrams should be made on a large scale in order to better 
 illustrate specific points in question. 
 
 Models may be made to show parts of the mine, the com- 
 plete workings, and the relative position of openings, excava- 
 tions and property lines. Models should be on such a scale 
 that dimensions can be readily appreciated. Only openings 
 may be shown, or, the entire territory and ground included 
 may be represented by wood or glass. Sedimentary deposits 
 sho'uld be represented by sheets of glass or wood which can 
 be easily handled and placed together to show actual con- 
 ditions. A skeleton of sheet metal, wire or tubing may repre- 
 sent the various openings. Sheets of glass may be used to 
 represent the veins and excavations shown in colors on the 
 glass. Vertical or horizontal sheets of glass may be used and 
 after the shaft has been located on these the adjacent workings 
 may be be projected. 
 
 CALCULATION OF VOLUMES AND ASSAY PLANS. 
 
 The estimation of volumes and tonnage of ore in place 
 or in stopes is one of the most important parts of a consulting 
 engineer's work, and he must adopt a system of work which 
 shall be rapid and at the same time sufficiently accurate for 
 his purpose. A good engineer cannot be satisfied with any- 
 thing but absolute accuracy, but generally sufficient time is
 
 A STCDY OF MINE SURVEYING METHODS 
 
 not available for the most accurate work. Chapter XIII. of 
 Johnson's Surveying is given to a consideration of the most 
 accurate methods for the measurement of volumes, to \vhich 
 work the student is referred. Practicing engineers persist 
 in the use of approximate methods, among which the most 
 popular is the one known as the "mean end areas formula'' 
 which Johnson condemns. 
 
 In behalf of the prismoidal formula its extreme accuracy 
 is urged, while in behalf of the mean ends formula its sim- 
 plicity and rapidity in use are undeniable. In mining work 
 it is not possible to get frequent cross sections. In estimating 
 ore bodies, unbroken blocks larger than 100' x 100' should not 
 be considered when it is known that the ore body is not reg- 
 ular. Winzes, raises and drifts should be driven to divide the 
 ore body into small blocks. Each mine has its special problems 
 and no fixed rule can be stated, only this, always underesti- 
 mate the tonnage in blocks of ore. In all cases an accurate 
 map, about one inch to thirty feet, should be used and meas- 
 urements of the vein and ore body taken every five feet for 
 accurate work. Such measurements should be noted on the 
 map at the point corresponding to the place where the meas- 
 urements were taken. Samples should also be taken at these 
 points. Methods of sampling cannot be discussed in this paper. 
 Almost all the mines of the Rand keep assay plans. An assay 
 plan of a mine is any map, not necessarily a plan, which 
 shows accurately the dimensions and value of the ore bodies 
 at such intervals along drifts, winzes, upraises, shafts and stopes 
 that an estimation of the value of the ore in the mine is pos- 
 sible. Where the dip is steep it is more convenient to use 
 the longitudinal section, because the levels on the plan would 
 be too close together to allow the figures to be distinct, but the 
 horizontal projection is more generally used because the samp- 
 ling follows the irregularities of the vein which do not appear 
 on the longitudinal section. The best projection, however, 
 is that of the vein itself. 
 
 Various terms are used in stating the amount of ore in 
 a mine. Practice varies so much, however, that it is not for 
 such a paper as this to review what is recommended in different 
 mining sections. The recent edition of "The Sampling and 
 Estimation of Ore in a Mine" by T. A. Rickard ?s suggested 
 for a careful study of recent practice. 
 
 The following terms are defined by various writers: 
 
 Ore developed, that which is accessible for measurement, 
 sampling and full examination on all sides. 
 
 Ore developing, ore exposed on one side, on two sides, 
 or on three sides. 
 
 Ore expectant, that which will probably be exposed in
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 
 
 the later explorations when it has been shown that the ore 
 shoot is of fairly uniform dimensions and value. 
 
 To enter into actual calculations a block of ore must be 
 exposed on three sides. When exposed on three sides, if the 
 ore body is fairly regular, the extremities of the lines not con- 
 nected may be considered as the limits of the ore and a plane 
 projected through these points. When cut on only two sides, 
 again a line may be drawn inclosing the triangle and the ex- 
 cluded ore body taken as probable ore. The calculations are 
 based on the theory of averages. The geometrical mean is 
 determined for thickness of vein and value of the ore in ounces. 
 The so-called foot-ounce method is thus developed. That is, 
 suppose samples be taken as follows: 
 
 Width Assay Foot ounces 
 
 4.4 feet 2.35 oz. per ton 10.34 
 
 6.2 feet .45 oz. per ton 2.79 
 
 7.6 feet .62 oz. per ton 4.71 
 
 4.0 feet .80 oz. per ton 3.40 
 
 "2272 feet TT27 oz. per ton 2~T724 
 
 The assay per foot of width is .96 oz. per ton. This method 
 
 may be applied to any number of samples, samples being taken 
 
 a uniform distance apart. This method has been worked out 
 
 by calculus and demonstrated by Mr. Hoffman.* 
 
 In the calculation for tonnage the cubic feet of ore are 
 converted into tons on the basis of a certain specific gravity. 
 It is well to determine the specific gravity of a large sample 
 of ore and determine the number of cubic feet necessary to 
 make a ton of ore, instead of guessing the number of cubic 
 feet to the ton.** The summation of the tonnage in the num- 
 erous blocks of ore will give the total tonnage in the mine. 
 NUMBER OF CUBIC FEET PER TON 
 
 MATERIAL 
 
 Number of Cubic Feet of 
 Solid Material in Place Per 
 Ton of 2,000 Pounds 
 
 Theoretical figure 
 calculated from the 
 average specific 
 gravity (for pure 
 unad'lt'd spec'i'ns) 
 
 A Figure 
 for Practical 
 Use 
 
 Galena ..^- ^' * 
 
 4.3 cu. ft. 
 6.4 
 8.0 
 6.6 ' 
 8.4 
 11.4 ' 
 11.9 ' 
 11.9 
 12.3 
 10.7 ' 
 11.1 
 11.4 
 
 4.7 cu. ft. 
 7. 
 8.5 
 7.5 
 9.4 " 
 12.5 
 13.6 
 13.5 
 14.5 
 12.2 
 12.5 " 
 12.9 " 
 
 Pyrite . . & . . . ./.'* .f^r 
 Blende M7-7 * /. -JC~" 
 
 Hematite ..../ ..%.". /trS^ 
 Limonite b (>.&. ?/.. . .Cffr. 
 
 Limestone Andesite Syenite 
 
 Vein Quartz Granite and Granite Rocks 
 
 Clay, Quartz, Porphyry,Trachytes,Rhyolites,etc. 
 Vein Quartz with 15% Galena 
 
 Vein Quartz with 15% Pyrite 
 
 Vein Quartz with 10% Hematite. . . 
 
 *"The Sampling- and Estimation of Ore in a Mine." 
 
 **From "The Sampling and Measurement of Ore Bodies in Mine Examinations,' 
 by Edmund B. Kirby.
 
 46 A STUDY OF MINE SUJtl'EYI.VG METHODS 
 
 The tonnage of coal in a tract may be similarly estimated, 
 it being unnecessary to consider the analysis of the coal. As 
 a rough approximation one thousand tons is estimated for each 
 foot of thickness per acre for a horizontal bed. The specific 
 gravity of the coal should be considered when accurate figures 
 are desired. 
 
 "Loose ore piled on dumps in pieces from head to gravel 
 size will have from 35% to 50^ of interstitial spaces, the per- 
 centage being greatest if the lumps are somewhat equal sized. 
 Thus a dump with 40% of spaces, and composed of ore averag- 
 ing 12.7 cubic feet per ton in place, will measure 21.2 cubic feet 
 per ton.'** 
 
 The mining engineer may be called to direct underground 
 operations of various kinds and in almost every instance careful 
 and successful work depends in a measure upon good surveying 
 and mapping. Tunnels for water works, submarine tunnels, 
 submarine pipe lines, etc., call for good maps and generally the 
 mining man is called upon to do the work. 
 
 Such varied work requires careful application to duty and 
 attention to details which are often neglected in surface work. 
 
 -O k \&*>^ ^BIBLIOGRAPHY. 
 
 VA ~*J 
 
 TEXT BOOKS ON SURVEYING. 
 
 Brough "Mine Surveying." 
 
 Carhart "Plane Surveying.*' Chap. VIII. 
 
 Davies "Surveying and Leveling.** Book X. Sec. Ill, IV. 
 
 Johnson "Theory and Practice of Surveying." Chap. XI. 
 
 Lupton "A Practical Treatise on Mine Surveying.** 
 
 Nugent "Plane Surveying.** Chap. X. 
 
 Raymond "Plane Surveying.** Chap. XII. 
 
 Scott and others "Mine Surveving Instruments." T. A. 
 I. M. E. 
 
 PERIODICALS. 
 Abbreviations 
 
 A. I. M. E. Transactions of the American Institute of 
 Mining Engineers. 
 
 A. S. C. E. Transactions of the American Society of Civil 
 Engineers. 
 
 Coll. Eng. Colliery Engineer. 
 
 Col. S. S. Proceedings of the Colorado Scientific Society. 
 
 E. & M. J. Engineering and Mining Journal. 
 
 M. & M. Mines and Minerals. 
 
 Min. Rept. Mining Reporter. 
 
 S. of M. O. School of Mines Quarterly. 
 
 *~Tbe Sampling and Measurement rf Ore Bodies." Kirby. Col. S. SL. Dec. S. 1S86,
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 
 
 REFERENCES. 
 
 Base Line 
 
 Establishing underground 
 base line, 
 
 Bobs- 
 Kind and weight of, 
 
 Coll. Eng. Vol. XIV, 92. 
 S. of M. Q. Vol. XI, 333. 
 
 Coll. Eng. Vol. XVI, 31. 
 S. of M. Q. Vol. XI, 333. 
 Carrying Meridian into Mine 
 
 See Connections, Plumbing, and Shafts. 
 Connections 
 Underground, at Leavenworth, A. I. M. E. Vol. XXIV, 25. 
 
 Through two or more shafts, Coll. Eng. Vol. XVI, 53. 
 Curves 
 
 On mine roads, 
 Depth of Shaft- 
 Measuring, 
 Inclined Shafts 
 
 Corrections for errors in. 
 
 Measuring through crooked 
 shafts with plumb line, 
 
 Surveying, without attached 
 
 telescope, 
 Lamp 
 
 Improved form of plummet, 
 Plumbing, of Shafts, 
 
 Hoosac tunnel method, 
 
 Comstock Lode method, 
 
 Montana method, 
 
 Croton Aqueduct method, 
 
 M. & M. Vol. XXIII, 280. 
 Coll. Eng. Vol. XVI, 53. 
 M. & M. Vol. XIX, 433. 
 S. of M. Q. Vol. XVI, 146. 
 Coll. Eng. Vol. XVI, 31. 
 A I. M. E. Vol. Ill, 39. 
 
 Severn Tunnel method, 
 Sperry method, 
 Tamarack shaft, 
 In iron mines in Pa., 
 General methods, 
 
 Stations 
 In poor roof, 
 
 Surveying Methods 
 General, 
 
 In coal fields of Pa., 
 In iron mines of Va., 
 In the Rocky Mountains, 
 
 Coll. Eng. Vol. XVI, 52. 
 E. & M. J. Vol. LV, 81. 
 E. & M. J. Vol. LV, 79. 
 A. S. C. E. Vol. XXIII, 22. 
 S. of M. Q. Vol. Ill, 272. 
 A. I. M. E. Vol. XXIV, 29. 
 M. & M. Vol. XXII, 247. 
 A. I. M. E. Vol. VII, 139. 
 A. I. M. E. Vol. XXI, 792. 
 E. & M. J. Vol. LXXIV, 478. 
 E. & M. J. Vol. LX'XV, 749. 
 Coll. Eng. Vol. XIV, 92. 
 Coll. Eng. Vol. XVI, 31. 
 M. & M. Vol. XIX. 187. 
 
 M. & M. Vol. XIX. 247. 
 
 Coll. Eng. Vol. XIV, 10, etc. 
 Coll. Eng. Vol. XIV, 197, etc. 
 A. I. M. E. Vol. XX, 96. 
 M. & M. Vol. XIX, 241.
 
 /* A STUDY OF MINE SURVEYING METHODS 
 
 Telescope- 
 Adjustment of side, A. I. M. E. Vol. XXIV, 28. 
 
 Volume 
 
 Measurement of stopes, Col. S. S. Dec. 3, 1895. 
 
 Of small drifts and stopes, M. & M. Vol. XXI, 344. 
 
 Wires- 
 Kind and size of wires, Coll. Eng. Vol. XVI, 32. 
 S. of M. Q. Vol. XI, 333. 
 
 Illuminating, Coll. Eng. Vol. XIV, 92. 
 
 Coll. Eng. Vol. XVI, 32. 
 
 Inspection of wires, Coll. Eng. Vol. XIV, 92. 
 
 Location of four or more, Coll. Eng. Vol. XIV, 92. 
 Prevention of vibration, S. of M. Q. Vol. Ill, 271. 
 
 Coll. Eng. Vol. XVI, 31. 
 Suspension of wires, Coll. Eng. Vol. XIV, 92. 
 
 PROBLEMS. 
 
 The following are suggested in order to teach the student 
 graphical and trigonometric methods for solving mine survey- 
 ing problems. 
 
 Problems involving descriptive geometry to determine the 
 intersections of veins, the location of openings to cut intersec- 
 tions of veins and to locate openings when veins are faulted. 
 
 In all cases certain assumptions must be made: 
 
 a. Except in problems 4 and 8, the surface is assumed to 
 be a horizontal plane. 
 
 b. Veins are assumed to be planes of uniform dip. Intersec- 
 tions of veins are assumed to be straight lines. Except in "b" 
 of Prob. 3, thickness of veins is not considered. 
 
 c. Shafts on veins will be straight but inclined. 
 
 d. Except where the grade is specified tunnels are assum- 
 ed horizontal, also drifts. 
 
 e. Dimensions of shafts and tunnels should not be con- 
 sidered, that is, openings are considered to be straight lines. 
 
 f. All inclined shafts to be the shortest possible except 
 in Prob. 8. 
 
 In the solution of important problems found in practice, 
 the scale used should be such that the errors of plotting do not 
 materially change the results. 
 
 PROBLEM i. 
 
 a. Locate vertical shaft on line "a-b" to cut the intersec- 
 tion of veins. Find depths of shaft and distance on "a-b" from 
 A .
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 49 
 
 PROBLEM I. 
 
 b. At 300' from "A" on "a-b" is a vertical shaft 200' deep. 
 Find pitch of inclined shaft and distance on incline from bottom 
 of shaft to intersection of veins. 
 
 Draw to scale i"=3Oo'. Take ground line E and W. 
 
 PROBLEM 2. 
 
 a. Locate vertical shaft to cut intersection of veins. Find 
 depth of shaft and the distance and bearing of point to sink, 
 from "o". 
 
 b. At "o" vertical shaft is sunk to cut vein EF. From 
 this point inclined shaft is sunk on EF to cut intersection of 
 the three veins. Find depth of vertical shaft, also bearing and 
 length of incline, also the pitch of inclined shaft. 
 
 Draw to scale i"=3Oo'. Take strike of "a-b" as ground 
 line. 
 
 PROBLEM 3. 
 
 a. Locate by distance from "o" point on "a-b" to sink 
 shaft. This shaft inclined and the shortest possible to cut in- 
 tersection of veins. Find length, pitch, and bearing of shaft. 
 
 b. Call intersection "r". Part bounded by "xor" is ore. 
 Taking "xor" as mean section and 6' as average thickness, 
 compute No. tons of ore. Heaviness=i7o pounds per cu. ft. 
 Find length of "or" "xr". 
 
 Draw to scale i"=3oo'. Take strike of "cd" as G. 
 
 PROBLEM 4. 
 
 a. Horizontal distance from tunnel mouth. (Eleva- 
 tion 9653'), to outcrop of vein, (Elevation ii745'9), is 6000'. 
 Vein strikes X 30 E and clips 63 to the N\V. Tunnel is driv- 
 en N 25W horizontal. Find length of tunnel to cut vein. 
 What depth on vein, will tunnel cut vein, knowing that 1700' NE 
 from outcrop elevation is I2345'.9' and taking hillside as plane 
 of the three points given. 
 
 b. Same as "a" tunnel on 2.5% grade. 
 
 Draw to scale i"=2OOo'.o. Take G E & W. 
 
 PROBLEM 5. 
 
 a. Locate vertical shaft on Royal to cut intersection of 
 veins. Find depth of shaft and distance and bearing of point to 
 sink from "o". 
 
 b. Locate incline on Lotus. Find depth, etc. Same as "a". 
 
 c. Locate incline on Minnesota. Find depth, etc. Same 
 as "a". Scale i"=3oo'. Take G E & W through "o".
 
 jo A STUDY OF MINE SURVEYING METHODS 
 
 PROBLEM 6. 
 
 a. On the Lotus 200' N W from "o" an inclined shaft is 
 sunk 300' in length. From the bottom of shaft a drift extends 
 on vein N 75 W. At what distance from shaft should a cross- 
 cut be started to cut intersection of Royal and Minnesota. This 
 crosscut to be at rt. angles to drift. Find length of crosscut. 
 
 Draw to scale i"=3Oo'. Take G E & W through "o". 
 
 PROBLEM 7. 
 
 a. Locate vertical shaft to cut intersection of veins. Find 
 bearing and distance from "o". 
 
 b. Vertical shaft is sunk at x' to depth of shaft in "a". 
 At bottom of shaft crosscut is run to cut the intersection of 
 veins. Find bearing and length of crosscut. 
 
 c. Incline started at x' to cut intersection of veins. Find 
 length, pitch and bearing. 
 
 d. Locate inclines on: Gopher, Mt. Boy and Yuma, to 
 cut intersection of veins. Find lengths, distances and bearings 
 from "o". * 
 
 Draw to scale i"=3oo'. Take G E & W through "o". 
 Point x' is 300'. N 30 W from "o". 
 
 PROBLEM 8. 
 
 
 a. From "o" outcrop bears N 10 E and dip of vein is 45*. 
 800' up the hill the point "o*' has an elevation 300' higher than 
 "o". Find strike of vein. 
 
 b. From "o*' shaft is sunk on vein. From "o" tunnel 
 is driven on vein. Find point of intersection and lengths of 
 shaft and tunnel. . Shaft perpendicular to outcrop. 
 
 Draw to scale i"=3Oo'. Take G E & W. 
 
 PROBLEM 9. 
 
 a. Find point to sink by bearing and dist. from "o" to 
 cut intersection of veins. Call point "x". Find depth. 
 
 b. At "x", due west of "o" 5100', S 67 45' W 7850' from 
 "o" vertical drill holes are put down cutting a fault plane at: 
 1000', 600', looo' , resp. It has been determined that portion 
 above fault plane has moved perpendicular to strike in a south- 
 easterly direction along fault plane 500'. Find point to sink 
 as in "a". Faulting took place, then country eroded to present 
 level condition. 
 
 Draw to scale i"=3OOo'. Take G E & W through "o."
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 57 
 
 PROBLEM 10. 
 
 a. On intersection of Pilot and Mary inclined shaft is down 
 600'. On intersection of Orphan No. i and Orphan No. 2 
 inclined shaft is down 550'. As the air in both places is bad, we 
 wish to start an inclined upraise from one shaft to connect with 
 the other; this connection to be the shortest possible. Locate 
 points in both shafts so work may be carried on at both ends. 
 Find length, pitch and bearing of the connection. Reverse 
 \ traces on Orphan i and 2. Compare. 
 
 Draw to scale i"=:3oo'. Take G E & W through "o". 
 PROBLEM ii. 
 
 y 
 
 A vein dips 60, an entry js driven N 40 W in the vein on a 
 5% grade. What is the strike of the vein? 
 
 PROBLEM 12. 
 
 A drift on a 3% grade is driven N 40 E in a vein whose 
 strike is N 60 E. Required the dip of the vein. 
 
 PROBLEM 13. 
 
 A vein dips 45 to the west and strikes N i23o' E. A drift 
 A on the vein is driven N i63o' E. Required the grade of the 
 drift. 
 
 PROBLEM 14. 
 
 A vein dips 54 to the east and strikes N i845' W- What 
 is the bearing of a drift on the vein driven on a 3% grade? 
 
 PROBLEM 15. 
 
 I. The strike of a vein dipping to the S. W. 75 is S 45 15' 
 E. From a given point of outcrop, elevation 3629.4' the mouth 
 of a tunel bears S 40 10' W and distant 3000' on a vertical 
 angle of -2ioS^ The tunnel is driven straight, horizontal and 
 N I2i5 / E. '/^Required the distance from the mouthy of the 
 tunnel to the point at which it intersects the vein. -L 3 Assume 
 the tunnel on a 2% grade. iHJ'-What is the shortest distance 
 from the tunnel portal to the vein? '/ '^*- 
 
 PROBLEM 16. 
 
 A vein (a) dips 55 to the northwest and strikes N 35 !o' E. 
 A second vein (b) strikes N 35 10' E and on the surface (assum- 
 ed to be level) is distant from the (a) vein 800'. How far from 
 the vein (a) should a vertical shaft be put down to pierce the 
 intersection of the veins (i) if (b) dips 30 to the northwest ; (2) 
 if (a) dips 75 to the southeast and (b) 55 to the northwest. 
 What will be the depth of shaft in all cases? 
 
 ss*
 
 52 A STUDY OF MINE SURVEYIXG METHODS 
 
 PROBLEM 17. 
 
 A vein dips 43 to the northwest, strikes N 33 15' E, eleva- 
 tion of outcrop 914.6'. At an elevation of 869.2' and distant 
 from the outcrop 1000', an inclined shaft dipping 75 and bear- 
 ing N 5645' W is sunk to intersect the vein, (a) Required the 
 depth to which the shaft must be sunk, (b) Assume the pitch 
 of the shaft the same but the bearing S 89 14' W; what will be 
 the depth of shaft? 
 
 PROBLEM 18. 
 
 The surface has a uniform slope of 10 to the north. A 
 vein strikes east and west and dips 40 to the north. 
 
 (a) How far north of the outcrop must one go to sink a 
 vertical shaft which shall cut the vein at a depth of 700'. (b) 
 What will be the bearing of drifts on the vein driven from the 
 bottom of the shaft on a 3% up grade? (c) How far can they 
 be driven so as not to approach nearer than 100' to the surface? 
 
 PROBLEM 19. 
 
 The vein described in problem 18 is intersected at a depth 
 f<-. JOQO' by a vertical shaft. From the bottom of the shaft a 
 slope on the vein extends due north 600'. An entry is driven 
 on a 4% grade to the southwest from the bottom of the slope 
 for a distance of 4000'. Required the depth of vertical shaft 
 necessary in order to connect the end of the entry with the 
 surface? 
 
 PROBLEM 20. 
 
 The horizontal distance between two vertical shafts is 1000', 
 the difference in elevation of the collars of shafts is ^291. 4'. The 
 depth of shaft sunk from the higher point is 647.2' ; from the 
 bottom of this shaft a crosscut (a) is driven towards the other 
 shaft on a i% grade, 436'. The second shaft is 350' deep. Re- 
 quired the length and grade of crosscut (b) from this shaft to 
 meet the breast of (a). 
 
 fyVr^--^ . 
 
 PROBLEM 21. 
 
 Suppose that the lower shaft described in 20 bears S i94o' 
 W of the other and that the crosscut (a) is driven S 40 W. Re- 
 quired the direction, grade and length of (b).
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING jj 
 
 PROBLEM 22. 
 
 A vein dips 60 to the south and strikes N 70 E. Consider 
 the outcrop of the vein as 3650' elevation. 500' distant from 
 the outcrop and at an elevation of 360 i' a vertical shaft is sunk 
 to intersect the vein. From this shaft the mouth of a crosscut 
 tunnel bears S 60 E, 2000' on a vertical angle of 30. The 
 tunnel is driven N 33 W on a 2% grade to intersect the vein. 
 Required the length of slope on the vein necessary to connect 
 the shaft and the tunnel. 
 
 PROBLEM 23. 
 
 Using the top telescope: 
 
 (a) Elevation=876.42' 
 +V. A.=522 9 ' 
 
 M. 0=76.49' 
 H. 1= 2.58' 
 +H.Pt= 3.45' 
 r= .301' 
 
 M. D=Distance from axes of main telescope to point 
 of sight. 
 
 Required V. D., H. D. and elevation. 
 
 (b) Elevation=76i . 59' 
 -V. A.=6955' 
 
 M. D.=87.23' 
 +H. I.= 4.28' 
 H. Pt== 3.91' 
 r= .301' 
 
 Required V. D., H. D. and elevation. 
 
 (c) Elevation back sight station=647.9i' 
 Backsight +V. A.=592o' 
 
 M. 0=63.48' 
 H. I.= 4.21' 
 -H.. Pt= 3.19' 
 
 r= .301' 
 
 Foresight V. A.=57i9' 
 
 M. D.=56. 93 ' 
 
 +H. Pt= 3.21' 
 
 Required elevationl of foresight station.
 
 3V A STUDY OF MINE SURVEYING METHODS 
 
 PROBLEM 24. 
 
 Using- the side telescope: 
 
 Elevation of backsight station 426.81' 
 
 Backsight +V. A.=462i' 
 
 +H. Pt= 3.19' 
 
 vernier I924' 
 
 +H. I.= 2.26' 
 
 M. D.=98.23' 
 
 Foresight + Vernier (angle right)=T7648' 
 
 _V. A.=s648 / 
 +H. Pt= 4.16' 
 M. 076.24' 
 
 Required elevation of new station. 
 
 PROBLEM 25. 
 
 , t ' 
 
 It is impossible to place staging- in a shaft and the second 
 level is not visible from the first level. In order to save time 
 underground, three points in the shaft visible from both levels 
 are established. The following notes are taken (using the top 
 telescope) : 
 
 Sta. Pt. Az. M. D. V.A. H.I. 
 
 100 100 a 298 35-04' 892o' 3. 91' 
 
 3-69' 
 
 a- C. -- C. 
 
 Required the distance and bearing of 200 from 100. 
 
 ioo a 
 100 b 
 
 TOO C 
 
 ioo a 
 ioo b 
 
 IOO C 
 O.-fr' 
 
 298 
 
 20232' 
 
 237^0' 
 2 97 i8; 
 
 35-04' 
 37-74' 
 36-58' 
 54-43' 
 51.82' 
 
 53-13- 
 
 892o' 
 87 4 i' 
 88 10' 
 
 +54>V 
 
 + 53 o6'
 
 AND THEIR APPLICATIONS TO MINING ENGINEERING 
 

 
 TABLE OF CONTENTS 
 
 PAGE 
 
 Introduction 3 
 
 Definitions . . . 3 
 
 Importance of Mine Surveying 4 
 
 Difficulties 5 
 
 Notes on History of Mine Surveying 6 
 
 Instruments and Equipment Used 6 
 
 Surveying Party 1 1 
 
 Underground Stations ..12 
 
 Base Line 22 
 
 Carrying the Level and Meridian Into the Mine ... 23 
 
 Underground Traversing 29 
 
 Surveying the Mine 31 
 
 Geognosy 33 
 
 Surveying Drill Holes 34 
 
 Locating Openings and Mine Plant 35 
 
 Shaft Sinking. . 36 
 
 Tunneling 37 
 
 Mine Workings 38 
 
 Curves and Connections 38 
 
 Openings to Intersect Veins 39 
 
 Geological Irregularities 40 
 
 Drainage 40 
 
 Haulage 41 
 
 Mapping and Models 41 
 
 Calculation of Volumes and Assay Plans 43 
 
 Problems 48 
 
 Bibliography 46 

 
 Date Due 
 
 JUN 7 1977 
 
 JUN 31977 
 
 The RALPH D. REED LIBRARY 
 
 DEPARTMENT OF OEOLOGY 
 
 UNIVERSITY of CALIFORNIA 
 
 LOS ANGELES. CALIF. 
 
 uNiYERsrnr L oF CALIFORNIA 
 
 LOS ANGELES
 
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 Library 
 
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