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This Proof la sent to you for discussion only, and on the otpress understanding that It Is not to be used for any other purpose whatsoever — v,,- .svi- 39 of llie Ciiniiiiiiii.'ii) tfnniiaian >ofiftit of tfivll tfufllnrrrs. INdilll'dllATKI) muT. TRANSACTIONS. N.H.— ThlMSoi'itty, IIS li hn.ly, (ioe» i"it Ik>IiI iti'i'If icdpongllilo for the factn Aiitl o|)lnioii .-•tulLMl 111 tiiiy of lin |tul>lioHtli)tiH, CONl'HKri'; AS A sntSTlTUTK FOIt MASONllV IN liKIIHiK WOUK. Ih .M. Mriii'iiv, M. V.m. Soc. C. K To bo rcaa Thursday, Pabraary the 23rd. For tlic liisl li "( vi'iir- tlic iiiilliiir liin bucii iisiii;^' coiidreti' us a siib- stitiiti' liir iiiiHimn, with a liiir (lc;;tvi' nl' .siicci'S^. With a fow iiitro- iliu'tnry "lisurvitinris. Ills |iap.'r will Iv ciiiiliiii'd (o iviniirks oil tbo theory and prarlii' • ol' I'oilhiinl Ciiin'iil roiicn'ti' a- a liiiildiiii;' iiiatiirial, and to i|J I'liiiijiiMiii'iil ill tin' rniiiiniclioii of lii'jiuvay hridL'i'j<, and otf r'r works rciiiiiiisj wilhlii tin' ^cn|ll• of hi-i own ^npirvi-ioii in tho J'rovii;ce oi" Nova Sfotia. In Nova Scotia, as w.ll as in oilier new eonntrii", the iuiproviaed wooduii bridges of the early settliTs sii|>|i||eil tin ir wants for crossiii;; rivers and streams, and, as at .aeh siiee.s-ive si;ii,'i; of priijrres.i their uiinibers necessarily ineri'iis,.d. tlie disiialjiiiiy of niore peruiaiient con- striietion beeaiii'- more and nior<' import. int. Tjie freipient replacement of these timlier slinetnr.'s t i.\ed tlie I'l-oviiieial lesmirees to such an extent, iliat It Ik eaine urgent to adopt m 'aiis whereby the aiinnal drain oil the ri'venne for their renewal and inaliil<'ii iiiee miLdit be lessened. In ISH:!, an Aet aiithoil/.iiiLr a Proviii.-ial Iman of siSOli.OOl) was passed for rehnililiii^' the oM wooden hri.li's where advisable, with mat 'rials sneli a- stale aol iron. Kne iiira'.'e I by ill" siiee.'s-l'ul oper- ation and results nl'tliis mea-iliv. the tr ivenim 'lit pi'.niiled two farther grants ,,1' §2r(II.Htlll e;ieli, In ih,' years IS-Ti and ISS", re,-.peetivoly, makilu on" million of dollars availalile towards reiiiilldiiiu^ those brid',;es iu a more snbstanlial form. I')veii with the additional voles of the two year.% last iiained, IWi. thirds of the highway br.idges of the whole Vmviiie ' could not be eri'etecl in the permanuni manner eoiitemplated. Nor was it desirable lliai tlii'y 1 louhl all be erected of iron supor- striieture, because there wi'ro many instances where wooden structures or cheap pile hrid^'es could subserve more ceoiKoiiiea'dy and aecoinimi. date equally well the piihlu' ivipiireuients. In positions favorable for solid fcFiiii latiiais; in places where rapid enrrents aii' spannetl; in situ- ations proni' lo ice-jams. iic,','ssjtatiii_' loii.'er ^paiis ; and in saline water where the /(/■../.« ii'irnHs or the liijiiiirin tiijii'iiiiiii an' active, all things else beiiii; eipial, iron lirld'j.'s on stone i-oneret ' and iron sup|Kirl.s were preferied. whilsi in |o,;ii;.iii- of an alluvial nature, in peaty or marshy de|Ki!its, or in ipiick.-aii I-. lO- wh le fre.^li water streams keep aloof or exclude tlio-c dcstructi\e a'^cnt^. an I when arlilicial loiindaiions would he iieeessaiy. hot ton e.\peii>ive, wooden slioetores or cheap pile lo'idges or other brilui's of w^iid soiled to the situation w.'ic adopted. In earrviieu 00' :lie polilic wca'ks in aoycoinii-, ii h di'iiiahle as far as pos.-lblc, to n~c the material of tic di-lrici, iiid thini^h Nova Scotia can I'urni-h both lice .s| in ■ and ',;iaiiite of e.\celleiit (|Ua!ily, it cannot furnish eitlnr of iheni. in the loaiioily of iii-iatiees with the means at the dispo-al of ih ■ .iiijiiic.r. If -tone Miitahle I'.ir uiasonry could be had ^o that ih.' vv^'ik 'OuM he p rloriijcd lio' eijil in' nine dollars per cnhie vard. t'^a! oiat.i-ial was invariably usi li ; if it could not, coiicretv was -nh-liliiled. In the eoii^tni.'tion of •lie>e hiuhvvav 01 pnlilic roa I lo idi:i's. concrete has borne an ini|iortant p-irt. It was ui tir-t — in IS8 ! — I'inploycd spariii;;lv and with lies|iiiii,,|i. hut ol late it has been used largely and with luu'h conlideiee. It- os,-. fm the support of the superstructure cif iron liiid^i'-, was pvoinpled by necessity, b.'i'anse of tli ■ scarcity of material.^ suit d for .i-hlar iiia- 'iiiy. the co t of lr.iii~p otation, the want of skilled workmen, aiel the rapi'lily with which it could be erected with ordinary labio. Tlii> leads to the nil re Hoiicliale ohjiei of this pap r, vvhieli is to intrii'liiee ti. the ic- of tic S.uiely vvliat h i< l^'cii iloiie in N()v» Scotia towards ihc soli-i union ol' eon rcie for luaMiiiry, and the results so liir observahlc. The iiitroilueiion of concrete wa^ at lir-t Ireal 'o as an e.Kpeiisive iiinovatiiMi. It was uol cxpccl d to r coivi' favorable public considera- tiioi. and it diil not. it was allcicd that in the climate of Niiya Scotia it wax un iv , .uuutublo intruMnii nnd would not "iiit its intondi'd pur- poM', mill :illlioui:li it I'oiild not bu Miiil to be nil i'X|K'timi'iit, bi'iauni it liuil bicii u»i'd so lurgiily in ntlior enimtrii'n, Htill it was I'lmiiiu'iittJ u|imi witb ilist'liMir. Niivrrtbiloss, concri'to piers lm»o bi'i'ii erected in tbe uiii>t rxpi'HciI |iositinii'<, in the mid^t of utroiig currents, ititlnnit any uxtL'riiul coaling of wood or stone, wliere they are exposed to ice-floes, to bliiw- rnuii timber drives, uiiil in some iostanccs, to iiiiileriniiiing 'y scour, witli coiniianitively lavimible results, Kxposun to sudden all.'r nations iil' leiupeiiitiiiv \viH so I'ur produced no visible daiim;:iiig eH'eit. Violent lilows sirike more impotently than upon masonry, mid ii U not so liable to rr.i;;nieutiii y sli]is or segregations because of its luoinilitbic character. Out of forty four iron bridges, with spans v:iryiiig from 50 to IGO feet, supported by concrete piers thus expost^d, there are Ibree piers showing inerWs of abrasion, but not to such extent a-i to need repair. Two o»' tliesei defects are traceable to faulty woikinaiisliip and poor uiaterinl. The third one. however, exhibits uiiiui>t:ikal>le symptmiis of disint"gi'atioii, anil roipiires special notice. It will be ref rred to fui- thcr un. The abutiiicnis and piers wore erected within a skeleton frame work cliwcly boarded against the face ns the work proceeded upwards. Tley were built id' Portland cement rubble concrete faced with I'ortlund cement fine Clllle|•ct(^ The facing of fine concrete was generally six inches in tbiukness, but varied to a width of nine inches in rapid enr rents or wbeie liable to more severity than is due to ordinary exposure. The I'ortland ceiiniit rubble concrete was composed of one part of gravel or small stones mil excceiliiig one inch in diannter. five partj* of large stones, weighing 'J(l lbs. iinil upwards, two parts of sand. ,iml one part of I'orllanil eenienl. In mixing the eonci'i te, tlie gravel, sand, and cement were turiieil over three times whilst dry. Water was then added and the neiterial aiiaiii lurnid over at leii.st three time- and well aggliimeraleil before beiin; placed in the work. The grnvel. .sand, and Portland ciuienl for the fine cuneiete were first mixed to form a matrix or body of eonereU-, and the large stones of the rubble eonerete wen.' placed tliereiii by hand. These stones were placed end upwards, two inches apart, and the spaces Is'tween tlieui grouted up .solid with lb" matrix to form a eompaet mass, and any liob's or cavities in the work were run full and tbisli wiib Portland eenient conipo, eoli-istiiig of two parts of sand and one of cement. The fine concrete facing was kept at least six inches higl^er than the rubble concrete, and united with it so as to form one homogenous mass. In every iii.stanee the lo|i of the pier or abutment was lini'-bed with fine eonerete for a depth ol' one foot six inches, and the shues of the iron truss posts were laid thereim without the usual bridge stats of stone. The width of jiiers at lop finish varied from three tiet to four li'ct six inches, iieeordini: to the superincumbent Weight they Imd to bear. In piers of twenty f el in lieivht the leirdening or '' set " wns .sulfieienily rapid to allow six laborers working on eaeli pier to pnieeed to com|i|etion without iulermission, ibe progress being from two to thiee cubic yards [icr man per day. The eonerete work tin the last three years has been executed by the Government's own eiiL'iuferp and wovkuien, without the inlerveiilion of contractors^ n sy.stem which, however iniipplicablu in some countries, has been found to answer well in Nova Seoiia. Upon the proper eom- pusition and incorporation of the ingredients which enter into ti.' con- crete, and which are mixed up and set with the rubble stone in the work, will deiHUhl the re.piisite adhesion and stability, :inil allliough reliable contractors wi're always available, still it was eonsiden d more advisable to carry out the work by men working by the day and trained under proper supervision until they become snffiineiitly skilful and ;is interested as the eniiineer in the sneeess of the undertaking. A lliO feet ."jian, 15 feet roadway, loadcl fiO lbs, per .-.(lUNre foot, | weight of bridge and lend =7t)U(Kl lbs. Taking this «iif;hl distributed over an area of thne feet sipiare by the liuil plates, and the euhesiiin of the cement itself, we .-hould have a weight supported ei|Ual to about 51 pounds Ut the si|Uare ineli, or tjuite within the margin of salety even for comparatively freshly .set concrete. Since an abiilment, to fiiil only by reason of a direct pres.-ure I'rnni the weight of the bridge, could only do so by the crushing of the p.irtieles of eemeiit together, and since this crushing could not take place witliout first rupturing the f ice of abut- ment at ii.s point of least resistance, wc may like this jioint as a mea- sure of our bi'iiring eipaeity, that is, lake the dislanee liom centre of pressure In nearest face of iibutmiiil us one half of our .ivailable widili and llii' width npiared Jis our Ixaring area, b'or a bridge of ibis size the wiilili lliiis loiiiid would not be less than fair fit. u'::\ the ili>tri- buled wi'iglil uiiiild be '.]',', lbs. pir sc|iiare im h on ibe walls, whieli are biitleii'd 1 in (1 or 1 in .'<, The use of eoncrele fur imr f;Mnnil VMirk in Nova Seotia eouimi need with the tilling in of the voids in enb-work abutments constructed of i.lo»p(l fiicod tlnilxT wnric . It «•«» noxt. oniplovi'd oi mnmr for nbuf- iiieutH mill l)rill^r for tlio building oCiirchcd brid'joii. Kxiiuipk's of iibutmi'nlH and piiTs of con- crete work can now be wen in every county in the Province. The rctaiiiin;; wall is bnilt with ultrnatin); arched panels ami bnttrexfics. Jt utandit in front of the Provincial liiiihling in the <'ity of Ilalifix, i.ii arched conrret set llakcy as the work went on. Kacb course was mouliled on the; iaiigi'ig of centers, i)y securing thcron a board in the true radial line between soffit and extrados, and the concrete was placed therein in its final |«wition lo form the conr.se. When suffi- ciently set the board was removed ami placcnl aijain for the next suc- ceeding course. A sctiing teuiplet, the same as masons make u.se of when laying vous,soirs or areh stones on centres, gave readily the in- clination of the board. The foreman in charge was cuutioiiermaoly and pro|uiitionately e(|uali2ed and adjust^^'d, The symptom of failure in the piet.i of one bridge already referred to, occurs in n lid:il stream at IVtite Hiviere, in Lunenburg < 'ounty. Two piers of enncriti^ supp'irt au iron bridge of 100 feet span. At low tidi' there is not more than one foot of wator. Ordinary neap tides rise five Icet, springs generally about six and one half lect. The outer shell or matrix of tine concrete, where exposed to the tidal fluctuations, exhibits fissiliiy, and will crumble at a slight blow. Above high tide it is solid and impervious. Two fragnu'nts cut from pier above and below tide ale exhibited fur examination. The bridge was erected in till! suiniiiir of 188,1. about eiixhtecn months ago. Although erected by a careful foreman and with the usual component parts of material for submerged work, viz., two of gravel, one of sand, and one of cement, it never attaineil the same degree of coherence as other work of the same chiiractcr, and it lias now become so friable as to point to the necessity (d' renewal at no very distant day. The concrete work in fresh water streams, as well as in sail and brackish water, had already given suoh I'viileni-e of {M-riii;in:iney that one Wiis loath to aekiiowlcflge a failure, or with M. Vieat, ascribe the result to the presence id magnesia in the sea WfttiT, ivliieh ai'ts injiiriou'-lv I'li the lime. In this instance the failure cannot b.' attributed ti carelessness in the selection and admixture of the eonert'te iiii^redicnts employed in buildiuir, because the disintegra- tion and hriith'iiess extend upwards only as far as the tides reach. Above that I'Vel it is "nmpaet ami firm. There is no sulphur or sul- phate iif lime in II. e neighlporhood. The gravel and sand are from the slates ami (|uait7.itis of the Lower Siliiviaii or Cambrian liirmation, the aurilerons rocks of Nova ,Seotia. Now I'ortland ecinent bning a mixture nf chalk and clay, which is supp .«ed to he burned to the extent of driving oft' the carbonic acid thus b' coming a hydraulic lime, nevirtheless through imperfect calcin- ation nriy not lorm a cement wliii-h would resist the action of salt waUr, allliou'jh it might succeed well enough in I're-h water. Again, if theiip WIS any sulphate of liiaif in the elay it would not at once enter into eomliiiiatioii with the lime, :iiid would he likely to cause the disiu- tegraticui experienced at Petite liivii're. If the material fVoui which the Portland cement is made was under burnt or imperfeetly ih eiuhonated, and contained an excess of free or disengaged lime, uhiih. not being uniteil with the silica anil ainminn, wniild ubsorl) moisture largily, and would fall lo pieces in water; in this ea-e. saj s .Mr. (i. V. White, the silicaU' of lime and iduniina had not hern formed, and the result would be an incomplete eemciit char- acterized hy a light yellow color, moderate specific gravity, imiiicdiato setting, and imperfect induration. Three hrii|niitis of the cement employed nt I'etiti' RiviiVe bridge, after se\en days' setting gave a tensile test of 320^, ;t58, and '.VKi lbs. res|)ectively to the square inch. The color and gravity were not noted at the time. Tho cement was quite fresh- 3 Portland ocumnt in nol nlwiiyH unifnrni : itM nmiiiirnoturi' n><)uire« uiucli t'lirt!; it id not friHi l'r»ui risk, tliou);li itt viii|ilnyiiiciit both in I'rinli (ind M'A wuti'r, jibovo anil bvlnw wiitor, is i.'<'iii'i'»lly xaiiHfactiiry, Thvro liiivt' bi'i'ii no viaibln ^i);n4 of ux|>iini*ion anil iniM'iiiHO of built, nr uunsiiiil oontiuctlon, wliivli in piixunmbiy otvinj; Ui I'aroful iuaiy MtiHim. KrnnviH, of Lnmlnn, in |iointin): and rcpairiii); the huh wiillx ruliiinin); tliu tiiibuiikinint »t llrity Ili'ud, on thu Itnblin. Wiuklow iind Wexford Hnilwiiy, nnd tliu m'ii wuIIs of tlio Dublin iind Kinf^xtown liailwuy, when re»idi'iit cnniMi'cr on tlioMi linen of riiilway, with n grciiU'r decree of Hueoiw thuD when I'ortland cement was euiploycd. 'J'be rapid Hot- ting of the natural cement proved more udvanlagenuit, up to the level of high water, than the too slowly mtting i'ortland or arti6cial eeiuent, during the oporition of tide work. It was considered better to erM|>lny both, ihe natural cement for jHiinting and lipping up to ordinuiy high water, and ihc artificial cement from Ihnt point upwards, and Ihe result aeeuied to justify the prnctice. When the exposed surface of the liasc of Ihe piers of Petite Jiivi(>ro bridge becomes more abraded, or when renewal is necessary, it is contemplated to submit tho Medina to a ■imilar test beside the Pr.'tland. There is at present an iron bridge under construction to replace the Victoria Bridge, Bear River, consisting of a swing span 100 feet in length, two fixed spans of 125 feet caeh, and one of 100 feet. 'I'hu owing span is to revolve on a circular pier 24 feet in diameter, entirely constructed of concrete. Kacli pier for the lixed .span^ consists of two wrouglit iron cylinders live lect each In diameter filled with concrete, coupled together by bieed ehannel beams and lateral bracing, and ■heathed between main tubes to prevent lifting or displaeement by iec floes. It is. however, the eireiilar or eonerete pier that comes more properly within the bounds of tbenr feet of the top, where they corbel t^i an apex and are covered with two feet of tine concrete. The swing span whi<-h is to turn on the centres, and is nni'lt^ to rexolve on live roller^, will be lifted on its center pivot by the nsii.il screw device or ceutral press, thus relieving tlie mllirs ol'pirt of tlieir weii'lit. There will be during the M|H'raiioii of turning 11S,,">!M) llw superimposed on the tiji'r feet M|ii.ire w:ill or pillar of eoiier< te, or .~>1^ lbs. to the si|Uaie inch. I'igure No. 2 gives the form and details of this pier With res|)ect to llie lliiei' fiel wiill siiiioundiii.: the piles under water, il will be filled up with enneiete loweied in paper bugs, each eonlainiiig a cubic foot of fine eoticr. t-*. Tlil> mode of plaeinj; eonerete ander water between piles, or within iron tiiUs where the iiiterteiiing spaces are small, has been priietisid in Nova Seotia very sueees.-fiilly. Tie iron tubes of the Avon briilgi', at Windsor, have been tilled up to the K \el of low water in this manner. The bags co^t ,^1 .3,5 per hundred or 36 cents per cubic yard addiiional li>r their use. They arc made of rough brown pa|ier well slifiVred witli glueose, which i> iinni'diately destroyed by immersion, the re^-idue helping to a-si^,t the induration and strength of the concrete, whilst there i^ v^ry little if any of the cement lost by BubiHcrgcnee. Hubble eonerete can also with care be placed under water in alternating courses of fine eon.TCte and stone, by lowering the stone so that they Would not rest against or upon each othiT and lower- ing a course of fine concrete in bags thereon. An objcotiiin mi»y |hmIiu|)'< Iw rRiwil to tlu' ciitMiliir |iior of N'ictori* bridgo iMjiiijt liiiilt »(' cnncrctc, mi tlii' (;rcmiiil llmt tlic [lierM iif tlm Pi'tlt*" Kiviirc lirilu;ii tli>>' uurri "• llio WimUir niul Aiiiiipiiiii Uiiilway over tliu Avon KiviT iit Windsor i^ iiu instaiu'c. Thu bridge is itup- porU'd by I'ijiht iiii'i'!* lUid two nbutiiuiilx of frwwtoiie anblar iii:iAonry, and CO icistt of iiiiio np hh of lattic trn^s, six of which aro ItiO ft. oaoh, tlio uttivr three, or iiliori< rt|ian!>, beiii); siiuilter. Thoro in very little water — not more llian from two to tliive feet — in the Ntreaui at low water. Neap tiilex ri^i' about 24 feut, ordiimry KpriiiKx four or five fcut higher. The pier.s of thin liriilge have been u Kouice of iinnoyaneu and expvnnu to the K:iilwiiy Company. The water peneiruten the body of tho inaitonry at high tide, and not being able to cMCapo 10* fa-t as tlio tidi' lei'edeH, or to i'iuffiei>'nt to justify the use of concrete as well as the introduction of the subject here. Iiocal conditions largely modify loeal architecture and re(|uirements. Down h^'re by the sea the Tren- ton limestone of ^loolT< al cannot be hail in adjacent (|Uarries, neither will till.' necessity of its ailuption warrant its introduction. Materials at home must suffice to supply the m'ods lit home If stone cannot be hail, or if it is of too rcfraetoiy a nature to bo made available, brick must take its place, and for the same reason concrete may in many situation:) be intn duced as a substitute: for stone as well as brick. Althoii'.di the history of rubble concrete dates as far back as tho his- tory of arcliiU'ctur.-, the introdiietion of Portland cement to the admix- ture of concrete may be saiil to be the history of our own times. lii KnglanJ, G.orgo iSeijple in 1774, i>r. Hi^-gins in 1775 to 1779, Sinen- lon ih 1750, ami I'arker in 179r>. by iheir respective investigations, reduced the practice of eoneieiiiig gravel wilh lime to a system. Sem- ple having stuilieil the woiks of Albert(^ who explained the system used by the aiieient li'onians in linildiu;; w.ills in coB'er dams or ou.sesof small nialeriais grouted, pioposeil U> t'ollcw the same plan in founda- tiins of bridges. I)r. Higgins' book on mortars gives the cflect of earth and inetallle oxi'le.s on Inmes and elialk limes, niii) on concreting gravel with lime I'or surfices of roads, etc. Hmealon's work on the Kddystone Ijighthoiise titu>;hl th<' propi'rties of English limestones and compared them with pozznolma and tanas, and I'arker took out a patent for making cements obiaineil from cirtain stones or argillaeeous productions or ni>diiles of elay. This stone was termed Sheppystone, from l».ing found near that i>lan(l. The >toues were burnt in kilns and afterwards giuiiiid lo powder. It wa." called Komau cement, and was us^'d in preference to .Mierlhaw, Hailing, ur Dorking hydraulic limes t^r cements. This Koinati cement w.is used almost universally until eclipsed by the rorthin I eemeiit of Messrs. Bazley, White & Co. In France and in llollaml the application of hetou seems to have been contemporaneous wi:h lOngland, and has Ijcen much more extensively practised in thu ereetion of inouolcthic structures during the present century. The report of the Jury of the Paris InteinatioiMl i'ixhibitiou of lSr>5 awarded .M. Vicat, a distingiiisle d l'"reiicli Kngineer, a " Mi.dal of Honor." and ob.served tint he had divotcd himself entirely to the study of the theory of the .'iction of limes with silicious materials, and had sueeessfully demonstraU^d that France pos-csscd all the elements of the pozzuolanas, and by the simple admixture uf calcined or raw clays with lii-e, artificial oeiuenis could be obtained for hydraulic pur- 5 p(i«'H. Iti' dini'iiiiT'il iiiiirly line.' Iiiiiiilri'd .|iiiinii>i< In Kniiioi' wlinirc liyilriiiilic ci'iiii niH vwM lie uliliiiiit'il. Till' iiijiiiil'iii'iiiri' lit I'nrtl mil ciiin'iit, lift culji'il iiiiitli'iol ociiii'iit. in iillriliutcil to i'X|iiiiiiii'iitH inn iii'.il in ISJii ly .Mnjiir-tl. ii.rul Sir ClmrliK I'unliA, iiii'l I'liiiiiiiiii'il tliniiiftli ii n't'wi nfyiMis.* li i< I'nin- |iiihril 111' tw.i Killl|i|i< iliL'l-nliillN, I'liiy iiinl cliiilk. ll I- |l iiii'i|i:i:|v luiiiiiirnftiiiuil nil llii' TImuiii" mill Mi'ilwiiy. In wliitc I'lm k ilbiiictH till' cliiy t'liiiiiM L'.'i |i> r iviif. til .'IK |ii r nnl. iil ilu' \v|i,i|(. Iniik. iiiiij in Kfry fliulk (listrirtw Hi In •_',■! |iir iHiit. .Mmli niri' in i'ii|iiiiv[:iiiiiil ill in iliiily iii;iiiiiliiiturr iiiiil u-i', i xti'inliiii: mil' ii iwriiiil oflit'ty yi'iirn. Mi'f-rN. Wliiti', 111' l/iiniliiii, wcri' tlm llrnt to ni'iki' iiinl intrmlin'i) tliii urtilk'iul i'iMii|Hiiinil us a ccuii'iit. Tlii'y, ImwcviT, iirls nl' Kurnii,', rnrlliuiil I'i'iii.iil munnl'ailnri'd in l':iif;liind was st.'iiilily LMiiiin^' I'lVnr, Imviii^ li vii nsid I'Xti'iisivi'ly fnr laiL',' hmliir and ilirli wnrks. Tin' I'XIi'iisivo a'ln|iliiin (if this iiiali'iial liy tin' .Mi'tiii|i,ili|^in llnaid nl' Wi.rks. in IS.js, in ih,' oniiMnii'liiiM iil's,'\n-i's, iliTw till' alti'iitimi nl' hji'^rini'i-rs In its vdiii' and iiii|ii.rtunn'. In I),., mlnr. Isi;,'). Mr. ,|,iliii tlraiit, M. Inst. i\ K , in nnc 111' till' ninst iiMi' ami .isrfiil |Ki|iirs ilmt lias ln'in written nn I'nrt- land i-i'UiiMil. (■iiliili'd " Kxin'rinii'iits im slrcn'^ili nl' renii'iil, cliictlv in rul'iTi'iiff tn tlin rnrihind I'liniiit ii.,il in iiii' ,> ill -iliiim III,' nmi',. till' slii'iii;ili iiirii'isis. ;!. JS'.'iit nniiiit is .slrniiLri'r than an adinlxtnri' with -and. I. Ci'iiii'iit iiiixid with mu', twn. tliri'i', ami limi- luris nf sand niav b" xaid tn !i,' at liu' .'ml „f nnr v.mi-. a|,|inixiinali'ly :|. '.. ' and \ ro.s- jiei'tii'.'ly nf ih.. >iri'ni;i|i nl'ni.al i-'iiii'iii, 5. 'J'hi' ili'amr .'iiid -iiar|ii'i' Ilm saml ih,, ,^i-,.ai.r ihi' slivn-th, li. Til" li'-s Hali-l i- ll~,-,| ill wnrkilln il lip III" Ili'lllT. 7. Sail wal.T is II- l; 1 Im iiiixiiiir rmilaiiil I'l'iinni as lr,.sh water. It is iiiiH iH.'iily.Vi'.u- .Hill'" .Ml'. IJiaiifs |ia|i.i' »a- |.ulilisli,.,|, and the rciilts Ihi'ii a iii.'iil am I'm- llm mn-t part in a.'.'nrd uitli thn I'Xjjeri.'iii.'.' nf Ill-day. 'I'li,. iiifnriii.uinii thus r,.ali/.i'd has iint niilv ii.ssislcd ill I'slalilishiiii; rm'lhiiid .'iimiil a- Imiiin ihi- h.-i fnr I'liiplnv. nii'iit wlmii' t;ri'.it tmiai'ily and pi'niiaiinii'y are iiidi-p"iisihli' r.'i|iiin'- nieiits, and ttlmiv hydi-.iiiiie pinpi-rliis ,ir,' d,.sirah|,.. Imi ii has ,ilsn eniitriliiil.il In raise the slandard nf il- iiiaiiiifaiini'i'. T|„. .s,.v,.ii i-.'snji^ i|Uoteil ahnvi' are pieked mil Irnni liv. nly Uvn nliiaiiiid frmn many ihmi Kftiids III tests, and lliii.r sil.it.d ale iiiiiiili..|'"i| aihiiririly I'm' ivlin-n,.,. Ilele. Tluy are. hnVM-HI. llle I'lslllls nf i\l,'li,f,l "Vpiriln. nl- wllli eeiii.'iil- riinii-hid In iii.'.l Ih.. r,-.|iiii','iii,.|ii- ,,| ,, |,|.^l, ..laii.lar I, where fnni mil. mils .,| l,ii-|„ 1- »,.,,. i;,,,, ,| ^i,,,! „|,,,v iii:iiiii('a"ni|.,.rs vie.l with laeh i.;l I r in ih. hiim mark, t in ilm pindiiiiinii ,,t the hest ma- terial nil ai- ml nl Ih" laii:" -a!i- alllleipal,..!. ■I'll,.,,. iv-i||(s s,.rv.) as lU'siruhle exam|ile^. Tin' ,|n,-i j., ||,,„ ,,, min,. .,, ,„. iimiiii,,!,, that di'.uri'e nf evi, lliih" hy iiii|i.'i..ii , |,.|.||.,i, |i i| i,,,.,,! j,., ,.,.. quired ill sullieieiiily laiL" ,|iiaiii ily li wiirnihl -hi| nt diri','1 IV,im the prndiiier. ih,. prnlil" 1' -, li'iimi, l„.,.,,i,„.. ,.,i-y. Ilm wlnii. in this e try. ll nvini'-r.ir eniiliaetnr wants I'mllaml ,.,.mriil inenm. paratively small i| Iitiis, ami Inn l'iei|ii,.|ii|y Hauls it imnii'diaii'lv. where the h.'st 1,-1- ,,f i,m,. .,||,| f,iiiiiiiy .ire nm ii\ailalil,'. h,.iii,,. i,,,, remote liir ininii di.il,' -,1, ,iinii. ili,. -,,|iiii,i„ h,.i'nnii.. mnr,. dillii'iilt. In thiii ease, in the liiimlil. npinii.n „| Ih,. wiilir, il wmild he .-al',r i,i ^eleel frniii a wi 11 kn.iHii Inaml nf a n-pi ,ta!i|" iiiaiiul'ai'liiii'r, than frmn any eniidiiimiiil ii.-i h,. i- awiin- i.f. There ar" at Imi-I iwn iii,|isp,.|i-ahl,. i,.-is wlii,.|i ,•,. ni i„i,si t„.,,r thuroinrhly Ijefmi' il eaii h,' pi a'", I :; I. Our is adlnsiv,' strenuth at various aL'es m'al and mixed, ihi' nthnr r.-istaiice In water. i'lin.,)ti.i reliH'iilp, liiurtavH, fit,-., by C W, I'lMlt.y, u * Villi" oliservatiiiiis mi li n, t-nl Loilfliill, IH.'is, Till' rnllnwiiii: iirr till' iisiiiil li'Hti ii|iplli'il, iiii'l lliry iiri' In MOiiie in HtullC'cn IllllrlillllUl, (ii) Kur lliiini'i'H liy Kirtiti)! mill rfkliliir. TIm' iiii|it I'm' nrlulil liii|H'rri'i'l ■ iliiiiallnii nr mi rxi'>i>H iil' liiiir, iir iiii in t'iMii|>l< li' lli;lil I'L'iiiiiil iviiiilil "Wi'Vir, III' iiiiiri' iiiiily |iiilvi'ri«i'il iiiiil Wnlllil U'i'i' II lllnr trxl ri'iilll IrxH ^I'ihilillg, (//') li'iir -livii'^'lli liy ln'riikiii^ or i ri'iluiii rinisliini'i' tn tiii»ili' ntruiii, Till' tiMt IVi'iii liiiiiui'llrn lllnr Inning Ihtii hrl. pi'vni iliiyn will In' in I'lviii' I'l'iiuii'k iiiilnriili wliiili i'- in il'"ir Mlijii'iiiiiiulilr; I'Xli'inl tlit' liinc III liiiir Hi'i'k', ill" ir-l will li>> linnul ini:r<' rrlialili'. If tin' I'l lit in I'liurwly >;riiiiiiil, rnn'< iil'linir limy In' injiirinut. (r) Ft wrivlii. Wiijjlii, K|K'i'iHi' nmvily, imJ I'liliir iiri! ini|nirtunt rli'Uii iitH. I'niil tin' Hiiniu inuiln ul' iiiwrtitininK lliii wi'IkIiI Ik innrn ^rniriilly iiil>i|ili'il, nl' ii inniii iinivTrKiil iui'Uiih i" I'Ktiilili.ilii'il w. iih not to III' iiir I till liy till' i|ni'-tion iix to wlii'llin tin' ti'ini'iit w.i'* inoK' nr Ii'mh riiin)iiii't in till' ini'.innri', llii' pii'ii'iit inriii" ol' ti'.ilin^ will lu' iinicliiilili' for I'lmiiiurii-on.* • Vl.l.i iviinlrKu i.( Mr. I''. 1. niiliiiii'll. |i. I.Ui. 1:17, vol. J:. rtilin. liiMl.C K. ((/) Ininnr ion in wiitir. Hy linikin^ two iiarln nl' I'mii'iit |iii»ti', lull' to III' |.nt in wnli'r, lIu' i>lli< r to li'' wt in tlir ami t as faeim-s ilet'T- iiinini.' nna-iir" of ailniixinre. ami Miloplini: llie tlieory of all ooo.l e.ineret". whieli i- lo "oai neiy |aitii'l" of -I ami i;r;v"l with a lilm of llie eenieiil. lie ili'lmlimi from llie the'ii\\ umili! b" that the inoiu iutiinale the nnii i llie mme perfect wmilil in- lie' eme'i'i'le resnltinj; from lb" e.nibinalion. ami sinee in a perliet S'orllanil eennnl the ail- mixlnre of liine anil eiay i-i) with neat e.-ment is sirnnuor Ihan an ailmixtnre with sainl. it follows thai tlm mine eeiiunl is eiuployuil, the stron'.;er anil better the eoneret''. N' \i lakiiij; ri>nli i I) eem. nl mixeil with an eipial i|iiantiiy of xiiol is I ol the sfen^lh ol 11. al eemeiit. with 'S parts A llie sireii;;lh, with :{ parls of s:niil J of the ^tieii^th, ami with I pails of s nnl ^. but with 5 parls of sanil il i~ abeiit ^t ul the strength of neat eeinent. It woulil appear thai the prupoitiun~ are maiiitaineil il|i to the inlermixturo with four parls "( saml. Imi vi ly pereeptibly losi's with a i;r"ater or tilth niiaxiii'". anil thi- foiiilh inteniiixinre is praelieally a proper limit. l''ine emierrt'' fur e.'vtiiii.il I'liipl.yim'iil in lliis elimate shoiilJ niit be innre than tlirie or fuiir parl~ of ;:r.iv.| lu uiie of "einent. With this prupurliuii a eoal ul suliil lini' will be ilepositeil luniiil eaeh praiii of s.iml ami Loavel. When Ire.-hly inixe.l eaeh pailiele will be enibedih'd in a .silnialeil sulnlion. If three to one ami line sharji saiiil is lined, till' iili-"r|iiiiiM III' llir (filler »ill I'liii-i' u I'liiilriiiiiuii, In iiinrUr, of IntWirll 'i mill I III ir< lilllk, hIiii'Ii will lllrii'iiKr ila Mijullly iiml ill.lW nil till' |Niiiii'|i'» iiijiilii I. Will II ill.' iimriar nr tine niiiiri'tii \» rluli iii |iril'ii'tly t'liiiniil ii iiniil llii> lliniiv litiiiiili tlir ti'»t nl' |iriii'tii'i', ila ilil |i I'liiiiiliilily III Hiiii'i' iHir ilii' Iniiili'iiiim nr urt " liii< liiki'u |iliii'» Ih'Iii;: u |iriiliiiiii'iit rmliii'i' St'llliin i'> llir mult nl' Imiir* or ilit,V'<, in- liuniliiui i* ilii' iii'tliiii III' iniiiiili* lui'l )'i'iii'>. iinkiii'^ iIk' iuikk kIIII i>ti'iiii)ji'i' ['Ji iiinl |iii'ti'iiliii^ iiijiiis I'liMii ill" r\|iiiii-iM' iiiltiii'Mi r ri'l'i'KlllU. !*<|iilir< >iillii'irllll_S nojlil illnl illl|H'l \ l.nl'i ||m'||i> Iti i. In li.' hiI'u rilllll l'ii|lui'l:lliiill ll> I'iikI IIIIIV Ii-' ^illi'l)' llll rn'llll'l'il llllii llli' lliiily "I'lllll iiiii"* III llir iiiniiiii'i' sliinii li) Ki^'iiic Nil ;i, hIiIi'Hii viT) iiiulriiiill iilt'i'i'liii^ It- -liiliilliN. wliiUi lit llll' Mini. tini.. liii'V l.irj;''!) I'linlillinn' til llll n|i .iinl liiiiii till' ili'»lnili|i' Iniik iitnl ir.liii'i' ll.i i'\|M'nililiiiii wiiliin |ii'ui'tii'iil i.ihI i.riin'.inii III liniil- ll U iilniiirl 11 iinit.'i.'iil ii|.iiiiiin lli.il r<.ili:iiiil nn I i^ Ir. i|ii. nlly i>|ii.||l in it" in.ini|iul.iliiiii (villi nllii'i' in;;ruilii.nin liy un i.kri.<»iil wiliT in llic inixlui'i' i.'i), 'I'lii- III. my is |iiiim'ii ||.:ii'iii' i|i_v Ii,\ uIiiiikI I'li'iy iiiHi niiinlilin^; ri'liniil piisl ' iiil.i lii'ii|iiullr>, Wlni'i' I'.iiiiirt.' ir. iiiiiii'il iiVi'l' iiii't iiiixi'il in tliiil^lis liy liinil, llic ililriin» liiliil nl' iivniilint; I'Xi'itli.ll ill iiiImiil; Ii\ I'l'lii'iltril '|.."i-. iif h .iliT. i-. Imi |i|VViili'lil 1111111I1.4 llll' Wl'lk ll llu' |iil-l,\ niulrnill i- I'.ii M.|lii'-it> I'l llll ll|i ;lll tlilili I'linml III" >liiii. •. .1 llll-" Mr»,'il I I'liiii.T.'il niiii|Bi ni.iv h" i.'.-ini.il i.. 'I'llix lull 'I' llli'l. Ill III i- .1:: ill -I til.. I I'll.' I III. 11 V III' r. 'II. 1. I. . ,111 I -ll.illlil ll ' >|iaiin',:ly iiml I'.iiriiillt .iiiii.ilii'i.l. i^iili « iliT I- 11- 1; I llll iiiiMir^ ri'illiiiiil ri'iiii'iit ll-. lii'-li Hiiii'i' (7 I. 'rill." ll|.iil'\ linlll" 'J I ill |irii'tii'i' Inl' I'lilli'l'i'ti' jllii'i'il III Mill Ullli'l, llwiii^ I" ill'' lri'i|ii''iil :.iii| iiliiininiiil ('li:iiui.» nl' li.|n|'i..riiliii'|. in iliu ('Inn III' nl Nniii Siniiii ill ill" ninniji. nl K'lii'.juiy unil Marrli, I'lllnr- cs.'ini'i' I- III. II li.'.iilil.. nil i'\| I Miil'.ii'.'- hIii'i. "ill wiili'i' liiis lien ii^i'.l in niixiiiL:. In llf n|Miiiiiii nl' tin' uiitlmi' fn'-li wuiir siinl anil lii'-li » .1 1 ai'i' I'li'l'iiiilil. . .11. 1 ili.'ii' ii-n ».iii|.| liki'lt li. iilliinli'il Willi lull, r li'-llll- III llli- inillilll . .•^11 inii.'li li.i> li'.ii -II. I ail. I iMill 11 ii'.-|n'i'lini; >la'j« iiiiil llii.'ii' v.iliu! in liyili'aiili" Ni'.il.ii. llial ll..' aiitliiir lia-. rii'iiiiU |iai.| -nan. atlriiliiiii til tlii'ir r.ii|.|.n,-.'il In ill. Ill 11' |.i..|i itii'-, mil ill" I'.'-iih li'Hi'- Hit I'' .Imilit nil Ills iniiiil Mill ili'V at.' 11. 't r lialil.' a- an liy.li'aiilii' ii^'i'iil 'I'lii' I'nllnrtini.' uiial\-i- "I llu' sla;j li'.iii ill" I'liiiiai'is nl' llin .Siin'l l'iiui|iany III' ('ana. Ill, al l.niiilwii.li'in , «.i- sii|i|.lii'i| li) .luliii .'^iiti'litl'.'. J')-i|., .M'iiiai.ir. I •-'.'1 ;i'j Silivu AIntniiia l''i null- Oiiiil'' MaiiL'.iniiii- tlxiil.' liiiii" .^lll'^lll'-ia I'ak'ii' .'^nl|ilii'lr I'nta-li ^'^nlla .■is.(n;i; ;i7.L'i .■ii;..iri :;7.hi :ir». t7 :■.;(. mi l.'l.'JMI ll,ll."l 1(1.71 'S.I.J III. . 'Ill ( ,| . (i.:;lii II. >ii I .llll I .ii.'i ii.i.iii ) 11. i^ I I 111 (I. II :;.."i."i '.'.T-'i I .till :;n. I i-s i-MiL' 17 llll iJ.ini i:;.7i ih.iki 7.111- I.-' I I III :i, i:; :;. i.i 1..M1 j.i.'il J .'.I'.i :i.i."i j.(i:i 1. 1 1 11,1:1 II. I),.- !ni.iiri7 !iii.r.i!i ii!i.."iii iiii(.4( !i!i.,si.' lis. in 1 tii-i'V -la'^. ,■>— tirnj >la;;. lint an. I lliinl li;! (ili'V llnllS -l,|.j, «llil.' I,!.." ;ir> till'} I'iii.l'r. :i7 (iri'J I'ill.ll'l. wllll' ll.'.', lint. Ilui.l ll'.l Wliil.'. V. lA .li;\ iiii.l.'i. 'I'll!' I'.Mlll- nl.tlililll linlll t.li'll.' I, '-I- 111 a l''',irl.allk s 'I'.-tillL' Mai'liitii' wire im li.ti.i iliaii a r.iiilan.l ""iin'iil iiiliiinixliiitj Willi sanil Wnlllil 111'. 'I'lli'V «' I'l' as InlL.tt-, — III III II, I'ul'i' L'llni'lil -.1 J."-ila)s lis .'iMI .'ill.'i I sla:; In 1 iiiin'iit •■ •_'■• ■• I'"-- -."i7 -S,s ■.' " 1 •■ ■■ L's ■ L'lJ Jl.-i -.M.-, ;t " 1 -7 7i' !ir. |n,; 4 •■ I •■ i;7 liiii ii:i 1-ji 5 " 1 ■■ n,; ;.^ ;, , (i •• 1 " •■ -s: ■■ s.; -7 'I'Ir' liall'.'l ..I -1,1^ ,-ii|.|.li".l. li.iiii wliii'li ih.' i.ri.|ii,.it,', »,.,,. n,;,,!,,^ slii-Hi'il til" silii'a ill .-I vitiiliil "..ii.liti..ii al-.i I'li-i'il -iliiai.' ..r lini,' ulrrailv rmt'ii'il witli tli" .iliiiiiiiia l.iiint t.. a hIiIi.' .Ir\ "iii.|"i. 'I'li"-,. lists will ll.' I I'lllll'.i nil ■^iryt an. I l,.avi. f sl.iu . II i- lln|i".| in liiiiu III sii|i|'li'in"nl till- |.a|"'i' «iili |."ii r ii'-ult-.