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 9
 
 Nicaragua or Panama 
 
 The Substance of a Series of Conferences made 
 
 before the Commercial Club of Cincinnati 
 before the Engineers' Club of Cincinnati 
 before the Commercial Club of Boston 
 under the Auspices of the National Business 
 
 League in Chicago 
 before the Princeton University in New Jersey 
 etc., etc. 
 
 and of a formal address to the 
 
 CHAMBER OF COMMERCE OF THE STATE 
 OF NEW YORK 
 
 By 
 
 Philippe Bunau-Varilla 
 
 Former Engineer-in-Chief of the Panama Canal ; Director of the Congo Railway 
 
 President of the Madrid, Caceres, Portugal, and West 
 
 of Spain Railways
 
 Nicaragua or Panama 
 
 The Substance of a Series of Conferences made 
 
 before the Commercial Club of Cincinnati 
 before the Engineers' Club of Cincinnati 
 before the Commercial Club of Boston 
 under the Auspices of the National Business 
 
 League in Chicago 
 before the Princeton University in New Jersey 
 etc., etc. 
 
 and of a formal address to the 
 
 CHAMBER OF COMMERCE OF THE STATE 
 OF NEW YORK 
 
 By 
 
 Philippe Bunau-Varilla 
 
 Former Engineer-in-Chief of the Panama Canal ; Director of the Congo Railway 
 
 President of the Madrid, Caceres, Portugal, and West 
 
 of Spain Railways 
 
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 113 
 
 I firmly believe that when the Truth is advancing 
 nothing can stop it ; I firmly believe that its irresist- 
 ible pressure will overthrow any dam of prejudice 
 erected In order to hold it back. 
 
 At the same time I think that individual efforts 
 may largely help the Truth in its progress, by clearing 
 from its path the obstructions of ignorance. 
 
 This was my aim when I answered affirmatively to 
 three American friends who invited me to come to 
 this country of free discussion in order to say publicly 
 what they had heard in private conversation with me 
 in Paris. 
 
 I am not here as the representative of any private 
 interest ; I came to defend a grand and noble concep- 
 tion which gave me several happy years of struggle 
 and danger, and for which I suffered many years of 
 anxiety, during which I do not remember one hour 
 of despair. 
 
 It has been to me a great privilege to have the 
 opportunity of exposing to the clear light of day all 
 the irrefutable facts which show that Providence has 
 subjected to a severe test the sagacity of man, by 
 giving apparently to the Isthmus of Nicaragua all 
 good qualities, and to the Isthmus of Panama all 
 defects for an interoceanic waterway, when in reality 
 it has given to the latter and refused to the former 
 all the attributes necessary for the establishment of 
 this natural highway of nations. 
 
 3
 
 I have been happy to speak in this great country, 
 where the first official word of justice for Panama has 
 come from the eminent Isthmian Canal Commission. 
 
 My purpose has been attained. I have worked for 
 the scientific Truth on one of those fields, where, as 
 Mr. Carnegie recently and justly said, there is no 
 room for selfish and private aims. 
 
 Philippe Bunau-Varilla. 
 New York, March 15, 1901.
 
 Gentlemen: — It will be my effort to lay before you 
 a series of facts officially or scientifically established 
 and to show at their clear light the real aspect of this 
 question of paramount importance. 
 
 Those facts, drawn from absolutely reliable sources, 
 will help to pierce the dense mist of prejudice and 
 erroneous impressions that floats over public opinion, 
 which was misled both by the deceitful appearance 
 of the natural conditions of the two canal routes of 
 Nicaragua and Panama, and at the same time by the 
 false idea that the Panama enterprise was paralyzed 
 by technical impossibilities, when, on the contrary, the 
 financial difficulties were the only cause of such par- 
 alysis, and came when, after a long struggle, all tech- 
 nical problems had been entirely solved. 
 
 It would have been a short time ago impossible to 
 make the same demonstrations with the same authori- 
 tative statements because, though the facts that I 
 could have brought had been the same, I would have 
 been obliged to place them under the authority of the 
 books that I published nine years ago, and I would 
 have hesitated to ask from you so much credit for 
 them. 
 
 To-day the situation is changed ; an official commis- 
 sion formed of the most prominent engineers of this 
 great country, so rich in eminent engineers, has thor- 
 oughly studied the question, and though they have 
 
 5
 
 presented but a preliminary report, which did not em- 
 brace all the points of this complicated question, 
 nevertheless the facts already definitively settled by 
 this hig-h court of technical skill are so numerous and 
 so precisely stated that a stable and permanent basis is 
 at last offered for a clear, open, and loyal examination 
 of the question. 
 
 In order to avoid any confusion about the au- 
 thority of the statements that I am going to make 
 before you I shall divide my speech into two distinct 
 parts, which correspond to two natural divisions, from 
 the point of view of the subject examined and from 
 that of the authorities which cover the statements. 
 
 I am going first to submit to comparative examina- 
 tion all the points that characterize the routes of the 
 Nicaragua and Panama from the point of view of con- 
 struction or operation. 
 
 For the first part I shall not give any figures that 
 are not extracted from the two American official re- 
 ports on the subject, namely : The preliminary report 
 of the Isthmian Canal Commission of November 
 30, 1900, and the report of the Nicaragua Canal 
 Commission, 1 897-1 899. 
 
 Onlv some fiorures referring- to the curves of the 
 Panama Canal, and which are not to be found in said 
 reports, will be extracted from the report of the 
 Comite Technique of the Compagnie Nouvelle de 
 Panama, made under the authority of first-rank engi- 
 rieers of America, England, Germany, and France ; 
 also some figures about the Chagres floods will be 
 extracted from public documents of said Compagnie. 
 
 In the second part the facts that I shall state in re- 
 lation to the stability of the construction are not 
 given under the authority of the Isthmian Canal 
 
 6
 
 Commission, who did not speak of that part of the 
 subject in the preHminary report, and some facts only 
 will be extracted from the report of the Nicaragua 
 Canal Commission. 
 
 Before going into the discussion let us first have a 
 look at the external appearance of the two routes. 
 
 Apparent Relative Value of Nicaragua and of 
 Panama Routes. 
 
 The Nicaragua Lake is separated from the Pacific 
 by a narrow Isthmus of 17 miles in width whose 
 divide is very low (44 feet above the lake), while the 
 Panama Isthmus is 45 miles wide, and its continental 
 divide 330 feet above the sea. This exterior aspect 
 is, I think, responsible for the false ideas formed in 
 public opinion about the easiness of the Nicaragua 
 Canal construction, because one is led to foreet that 
 the real and immense difficulties are not on the west- 
 ern side of the lake, but on the eastern side, in the 
 valley of the San Juan (120 miles long), which a 
 superficial examination leads one to consider as a 
 natural waterway between the lake and the Atlantic, 
 which it is far from being in reality. 
 
 Owing to that erroneous impression people gen- 
 erally believe that only a very short canal navigation 
 will be met on the Nicaragua Isthmus, and that dur- 
 ing nearly all the time of transit from ocean to ocean, 
 ships will float in free deep water. 
 
 PART I 
 
 Respective Lengths of Canal Navigation. — 
 There is an evident impossibility of utilizing the 
 lower half of the San Juan for canal navigation, on 
 
 7
 
 account of the immense amount of sand brought into 
 it by torrential and powerful tributaries coming from 
 the volcanoes of Costa Rica. 
 
 Mr. Menocal, thouQ^h abandoning^ the lower San 
 Juan, hoped to replace that part of the river by two 
 artificial lakes, formed by damming two northern 
 tributaries of the lower San Juan, the San Francisco 
 and the Deseado. 
 
 He further projected, in the Isthmus of Rivas, a 
 third artificial lake between the Nicaragua Lake and 
 the Pacific. 
 
 Those three lakes, as well as the San Juan River, 
 between the Lake Nicaragua and the Ochoa dam, 
 had to be kept at the same level as the lake itself. 
 This route seemed to transform into reality the ad- 
 vantage which the Nicaragua route appears to have, 
 namely, a short canal navigation, combined with the 
 long free navigation in deep water. 
 
 This is how it was often asserted that under that 
 plan, if not exactly 17 miles canal navigation, at least 
 not more than 28 miles had to be expected between 
 the oceans. 
 
 I showed in 1892 that this figure was much too low, 
 and that 85 miles of canal navigation had to be met, 
 if one takes into account all parts of the way, where 
 ships have to navigate in a channel dug either in open 
 land, or below the bed of a river, or below the bottom 
 of a lake. 
 
 I pointed out also to what extraordinary difficulties 
 such an extraordinary amount of damming would 
 lead, and the danger of receiving above the Ochoa 
 dam such tributaries as the San Carlos, with its enor- 
 mous amount of sand. 
 
 The Isthmian Canal Commission, and before them
 
 the Nicaragua Canal Commission, rejected the Meno- 
 cal plan as impossible, and thought that the first place 
 admissible for the location of a dam was above the 
 mouth of the San Carlos. 
 
 According to figures given by the Isthmian Canal 
 Commission, the total length of canal navigation, 
 under the plans they adopted, will be 120.53 miles, to 
 which are to be added 66 miles that will be made in 
 free deep water, either in river or in lake, making a 
 total of 186.53 niiles from ocean to ocean. 
 
 Of that total length of 120.53 miles of canal navi- 
 gation, 22.19 rniles will belong to an artificial channel 
 dug below the bottom of Nicaragua Lake, and 27.96 
 miles to an artificial channel dug through sand and 
 silt below the bed of the upper San Juan River, of 
 which the larger part will be more than 16 feet below 
 the natural level of the bed of that great river, which 
 carries in flood 100,000 cubic feet of water per second, 
 half given by the lake itself and the other half by 
 lateral tributaries. Outside of the channels opened 
 below the water, 67.33 rniles will be dug through open 
 ground, the harbor approaches forming the balance of 
 the total length. 
 
 The 66 miles of deep-water navigation are formed 
 by 48.74 miles in Lake Nicaragua, and 17.26 miles in 
 the San Juan, immediately above the dam. 
 
 Let us now examine the situation in the Panama 
 Isthmus as it will result by the project adopted by 
 the Isthmian Canal Commission. 
 
 In Panama we find but 38 miles of canal navigation, 
 to which must be added 7 miles deep-water navigation 
 through the artificial lake formed above Bohio, by the 
 dam projected there across the Chagres at a distance 
 of 15 miles from the Atlantic Ocean. 
 
 9
 
 In fact, the canal navigation in Panama will be less 
 than one third that of the Nicaragua route. I need 
 not say how much reality differs from the external 
 and apparent aspects of the two routes in regard to 
 lengths of canal navigation. 
 
 Depths of Great Cuts. — The continental divide 
 is in Panama, 330 feet above the level of the oceans, 
 and 274 feet above the bottom of the cut projected by 
 the Isthmian Canal Commission ; those measurements 
 applying to the natural and original state of the 
 ground. This is the so-called Culebra cut. 
 
 The work executed by the old and the new Panama 
 Company leaves to-day 1 10 feet excavation to be made 
 above said bottom. It is the deepest cut that remains 
 to be excavated on the line of the Panama Canal. 
 One sees to what to-day is reduced this terrible diffi- 
 culty of the Culebra, which was really the greatest that 
 the construction of the Panama Canal has met, and 
 which during the first six years of the construction 
 remained as an unsolvable problem. 
 
 I have related, in 1892, by what method I had been 
 able to meet that immense difficulty and to take it out 
 of the way of the construction of the Panama Canal. 
 It is to that task that I mostly consecrated the 
 last two years of my presence on the Isthmus of 
 Panama. 
 
 Let us now see what aspect the question of deep 
 cuts on the Nicaragua Isthmus presents. 
 
 On the Nicaragua route, we find that the continen- 
 tal divide is not the place where the deepest cut is 
 necessary. 
 
 As already stated, the cut at the continental divide 
 is insignificant (44 feet above the lake), but a high 
 cut of 297 feet above bottom and others of 218 and
 
 170 are to be met in the low valley of the San Juan 
 to go through high ridges projecting in said valley. 
 
 These facts show that most unexpectedly the Nic- 
 aragua location is, from the point of view of depth of 
 cuts, by far the worse of the two routes, and that the 
 ratio of I to 3 in favor of Panama is to be found 
 equally for length of canal navigation and depth of 
 cuts. 
 
 Dams. — I will not weary you about details of 
 technical descriptions as to the relative importance of 
 the two dams to be built, either in Nicaragua or in 
 Panama. Let me only say that the Isthmian Canal 
 Commission stated that the dam to be built in Panama 
 can be built of earth as well as of masonry, which indi- 
 cates that neither its difficulty nor its cost is extra- 
 ordinary, and that the same Commission, speaking of 
 the Boca San Carlos dam, on the Nicaragua route, said 
 that " the most difficult engineering work in connec- 
 tion with the Nicaragua Canal project is the construc- 
 tion of a dam across the San Juan River to holdback 
 the waters of the lake, and enable its level to be 
 regulated." 
 
 This dam would necessitate compressed air founda- 
 tions to a depth of 100 feet below low-water level of 
 the river, and have a total height of 1 50 feet from the 
 crest to the foundation. 
 
 The Commission estimates that eight years would 
 be necessary for its construction. 
 
 Chagres Regulation, — Let me add that the dam 
 to be constructed at Bohio (Panama) does away en- 
 tirely with this monster of imagination called the 
 Chagres. What has been said of the Chagres, and 
 the difficulty its regulation presents, has been im- 
 mensely exaggerated. The Commission has proposed
 
 to build a dam in order to form a lake whose normal 
 level would be at 85 feet above the sea. The out- 
 let of that lake will be 2000 feet wide, and the 
 surface of the lake combined with the dimensions 
 of the outlet are such that the largest floods ever 
 known will be incapable of raising the surface of the 
 lake more than a little over 5 feet. I do not wish 
 to enter into tiresome technical details, but I trust 
 you will accept the statement about the easy regula- 
 tion of the Chagres, because it is a conclusion arrived 
 at by the eminent American Commission itself. 
 
 We have seen when speaking of deep cuts to what 
 the Culebra difficulty, which was a great and real 
 one, is to-day reduced ; we have also seen to what 
 the Chagres difficulty, which was never a real one, 
 has been reduced. 
 
 Culebra and Chagres are the two names that sym- 
 bolize in public sentiment the impossibilities of a pas- 
 sage through the Panama Isthmus. Both of them must 
 be totally erased and disappear from the public mind. 
 
 Locks. — In reference to the locks which will be 
 constructed, it will be sufficient for me to state that 
 nine locks will be necessary in Nicaragua and only 
 five in Panama, and that the level to which the ships 
 will have to be lifted will be, in the case of the Nica- 
 ragua route, no feet at maximum, and, under equal 
 conditions at Panama, 90 feet. 
 
 The foundation of all locks in Panama will be on 
 rock, and only five in Nicaragua will enjoy such ad- 
 vantages ; the other four, says the Commission, " are 
 located on foundations that are believed to be safe." 
 
 Nicaragua Gales. — The winds in the Nicaragua 
 Canal location are exceptionally violent and per- 
 manent. 
 
 12
 
 This is the result of the geographical situation of the 
 San Juan valley, open to the trade winds and parallel 
 to their general direction. The lateral higfh moun- 
 tains of Nicaragua and Costa Rica form a barrier to 
 the continuous trade winds, which is only open 
 through the San Juan depression. Those continu- 
 ous and violent gales, much heavier than trade winds 
 at sea, will be a great obstacle, and a great danger 
 for navigators. In Panama nothing of the sort is to 
 be feared, as the Canal is in a direction from north- 
 west to southeast, perpendicular to the trade winds. 
 Lateral mountains shelter absolutely the Canal from 
 any access of trade winds. 
 
 Currents. — Concerning river currents, it will be 
 easily understood that, the San Juan River having a 
 much larger watershed than the Chagres, and the 
 Nicaragua Isthmus being much more rainy (from 2 
 to 2^ times more than the Isthmus of Panama), the 
 quantity of water, though its flow is regulated by 
 the Nicaragua Lake, will be much greater, and gen- 
 erate much more permanent and intense currents 
 than will be the case in Panama, where the great 
 floods of the river are of very short duration, and do 
 not occur at more frequent intervals than three years 
 or more. 
 
 To illustrate this state of things, the appendices to 
 the Nicaragua Canal Commission's report and the 
 official documents of the Panama Canal Company 
 give most interesting figures. From measurements 
 taken during ten consecutive years (1889 to 1898), 
 at Gamboa, at the beginning of the five miles where 
 the Chagres and the Canal will be in the same loca- 
 tion, the averagfe discharge of the Chag^res has been 
 3400 cubic feet a second, and the average discharge
 
 during the last six months of every year has been 
 4800 cubic feet a second. 
 
 Measurements taken in 1898 in the San Juan River 
 show that the average mean discharge above the 
 mouth of the San Carlos has been 25,000 cubic feet 
 a second for the whole year, and 31,400 for the last 
 six months. 
 
 This shows the relative importance of the two 
 rivers. And at the same time it must be borne in 
 mind that the rainfall at the Atlantic terminus of the 
 Nicaragua Canal at Greytown in 1898 was only 201.64 
 inches, while the other figrures oriven in the Nicarao;-ua 
 Commission's report are 296.64 inches for 1890, — 
 214.27 inches for 1891, — 291.20 inches for 1892, these 
 being the only years when the rainfall was reported 
 for Greytown. It shows that the figures above given 
 for river discharges in NicaraQ^ua are more like a 
 minimum than anything else and that probably half 
 more may be often expected. 
 
 In the same comparatively dry year of 1898, the 
 average of the maximum discharge of the San Juan 
 measured in every one of the last six months of the year 
 was 45,500 cubic feet a second, the highest maximum 
 discharge for that period being 70,500 cubic feet a 
 second, in November. (Measurements above mouth 
 of San Carlos.) 
 
 In the Chagres in the last twenty-one years five great 
 exceptional floods have taken place, which lasted only 
 a few hours and gave at Gamboa a discharge of 72,- 
 000 cubic feet a second in 1879, — 58,000 cubic feet a 
 second in 1885, — 58,000 cubic feet a second in 1888, 
 — 58,000 cubic feet a second in 1890, and 42,000 
 in 1893. 
 
 It is obvious that the great floods of the Chagres, 
 
 14
 
 which may be considered as an exceptional incident, 
 lasting for two or three days, and occurring at very 
 rare intervals, give about the same amount of water 
 if not less as the average monthly winter great flows 
 in the San Juan above the mouth of the San Carlos 
 River. 
 
 Maintenance of the Canal Channel in the Bed 
 OF THE San Juan River. — What will be the effect of 
 each flow on the maintenance of the canal channel 
 dug into the bed of the San Juan is extremely difficult 
 to calculate. 
 
 There is not a part of the technical science where 
 man feels more the weakness of human knowledge 
 than in such a question. 
 
 The form of the bed of a big river is the resultant 
 of the very complicated mechanism of different factors 
 associated together, namely, the amount of water 
 discharged, the variation to which the discharge is 
 submitted, the quantity of gravel, sand, or silt carried 
 by the floods, the relative densities of those materials, 
 the obstacles met by the river, the declivity of the 
 country on which it flows, etc. 
 
 It is impossible to calculate the part every one of 
 those factors has in the definitive determination of the 
 form of the bed, but it may be stated that when the 
 industry of man makes it necessary to change with 
 brutality the natural form of the bed, and to trans- 
 form it into a new channel, this channel, if in harmony 
 with our needs, is in absolute contradiction with the 
 natural needs of the river, and one may expect to 
 sustain with nature one of the most dangerous strug- 
 gles, one of those where man has been often totally 
 defeated. 
 
 A striking example of the variety of forms that a 
 
 15
 
 river bed can take is precisely offered by the San 
 Juan above and below its junction with the San 
 Carlos. 
 
 From the Machuca Rapids to the mouth of the 
 San Carlos, a distance of about fifteen miles, the San 
 Juan has a very deep bed, 40 and even 44 feet in 
 some places at low water, and very little fall, about 
 one foot for the whole distance. 
 
 Below the mouth of the San Juan to Ochoathebed 
 is about 12 feet deep at low water, and the fall 6 feet 
 for 3 miles. 
 
 The river is in that latter part twice wider (in 
 rough figures) than above the San Carlos mouth. 
 
 Of course the inclination of the water surface, 
 associated with its reduced depth, generates a sensible 
 current, even in very low water, below the mouth of 
 the San Carlos, while, on the contrary, the water runs 
 very sluggishly in the deep bed above. 
 
 On account of this sluggishness in that part of the 
 river, it was termed " Agua muerta" (Dead water). 
 
 The first impression given by the existence of such 
 a deep channel where water is very slow conveys the 
 idea that the river has been unable to fill up the bed 
 with sand or silt as it did below the mouth of the San 
 Carlos, and that therefore the waters of the San Juan 
 River are exceptionally clear. But a closer examina- 
 tion dismisses this impression. 
 
 It would be necessary to imagine that the San Juan 
 waters above the San Carlos are as pure as distilled 
 water, to think that in the course of centuries their 
 sediments could not fill the bottom of that channel. 
 
 The cause must evidently be referred not to the 
 scarcity of sediments but to the impossibility for the 
 stream to gain room in width on account of lateral 
 
 16
 
 obstacles. Probably no other way was left to the 
 river, to convey the mass of water that has to pass 
 periodically in floods, but to dig into its proper bed 
 a deep channel for itself. 
 
 As soon as the flood is over and the temporary fall 
 created by the very flood has disappeared, the river 
 takes a sleepy aspect which does not throw any light 
 on the quantity of sediment that has passed during 
 the flood, and that will stay in the bed if the nat- 
 ural conditions are altered by the intervention of 
 man, if, namely, the section through which water has 
 to flow is brought from 6000 or 7000 square feet to 
 40,000 or 50,000, as will be the consequence of the 
 construction of a dam raising the natural level of 
 Water about 50 feet. 
 
 Returning to the most important question of sedi- 
 ments, and after having shown that the " Agua 
 muerta" does not prove anything about their scarcity 
 or their abundance during the floods, let us see what 
 tributaries fall into the San Juan above the "Agua 
 muerta." 
 
 We see about thirty miles above the San Carlos 
 mouth a great tributary called the Poco Sol. 
 
 This tributary is set forth in the Nicaragua Canal 
 Commission's report as follows : " The principal trib- 
 utaries from the Costa Rican side are the Rio Frio, 
 Poco Sol, San Carlos, and Sarapiqui. These large 
 streams exert a controlling influence in confining the 
 location of the canal to the left bank." 
 
 In the geological report we find this river alluded 
 to as follows : " The San Juan River receives only 
 small tributaries from the north, while it receives 
 both small and large from the south. The large 
 tributaries include the Frio, Poco Sol, San Carlos, 
 
 17
 
 and Sarapiqui. These all head upon the slopes of the 
 Costa Rican volcanic range which forms the southern 
 margin of the Nicaraguan depression." 
 
 To judge the influence of the entrance of such a 
 stream in the middle of the section of the San Juan 
 which will be consecrated to canal navigation, it would 
 be very desirable to have exact measurements of the 
 volume of its discharge and of the quantity of sedi- 
 ments brought. 
 
 Unfortunately no measurements of that large 
 stream were reported by the Nicaragua Canal Com- 
 mission, as has been done for the three other great 
 and torrential tributaries, falling from the slopes of 
 the volcanic range of Costa Rica, namely, the Frio at 
 the west of the Poco Sol and the San Carlos and 
 Sarapiqui at its east, all three bringing enormous 
 masses of water in floods and enormous masses of 
 sediment. 
 
 In the absence of precise data some very probable 
 notion may be formed of the relative importance of 
 the Poco Sol. 
 
 The San Carlos has a drainage area of 1450 square 
 miles. The Sarapiqui has a drainage area of 1 100 
 square miles. The drainage area of the Poco Sol 
 has not been given, but the drainage area of the tribu- 
 taries of the San Juan from the Savalos River to a 
 point near and above the San Carlos is 750 square 
 miles. The only important tributary in that section 
 of the river is the Poco Sol, and its watershed may 
 be estimated with that of the Poco Solito as at least 
 between half and two thirds of the total surface. 
 
 One may say for the sake of comparison that the 
 drainage area of the Poco Sol is between one quarter 
 and one third of that of the San Carlos, that it comes 
 
 18
 
 from the very same volcanic region as the San Carlos 
 and flows on the very same ground. The natural 
 consequence ought to be that it brings a proportional 
 quantity of water and sediment. We have a state- 
 ment which confirms that view in what regards water 
 discharge. 
 
 The total discharge of the tributaries into the San 
 Juan between Savalos River and San Carlos River 
 was calculated to have been in 1898 about 4,500,000 
 acre feet, to which, according to the above estimate, 
 between 2,290,000 and 3,000,000 ought to have come 
 from the Poco Sol River. The similar figure calcu- 
 lated for the San Carlos proper is 7,661,000, of which 
 the third part would be about 2,500,000, an amount 
 which approximately confirms the above estimate. 
 
 We fail to see any material fact that could lead 
 one to think that a similar proportion should not be 
 the very same one between the quantities of sediment 
 brought into the San Juan River by the Poco Sol 
 and by the San Carlos. 
 
 Only the fact that the river bed is, for a distance of 
 fifteen miles above the San Carlos, deep and that the 
 San Juan River there is sleeping at low water could 
 lead to a different conception, but we have shown that 
 it does not prove anything about the amount of sedi- 
 ment of the upper river, and results simply from the 
 different factors that determine the form of the bed 
 and which do not allow any sediments to stay there, 
 but force them farther down the stream. 
 
 If such a proportion as three or four to one was 
 proved to be the real one between the amount of sedi- 
 ment brought by the San Carlos River and that 
 brought by the Poco Sol River into the San Juan 
 River, or even a much lower one, as the amount of 
 
 19
 
 sediment brought by the San Carlos River was consid- 
 ered as equivalent to a formal impossibility of maintain- 
 ing any channel in the San Juan below the San Carlos, 
 the maintenance of the depth and width of the canal 
 channel in the same river between the Poco Sol and 
 the San Carlos, which was estimated by the Isthmian 
 Canal Commission as being within the limits of prac- 
 ticability, could not fail to be an extremely difficult 
 one. 
 
 Most likely the exact determination of the water- 
 shed of the Poco Sol, from precise surveys in the vol- 
 canic region from whence it comes, as well as its mean 
 and flood discharge, and the appreciation of the 
 amount of its sediment in flood, as much as can be 
 done by experimental tests, will be found in the 
 definitive report of the Isthmian Canal Commission, 
 and will settle this very important point. 
 
 We shall finish the study of this chapter by saying 
 that even leaving aside the amount of sediment 
 carried by the river or thrown into it by its tributaries, 
 the maintenance of a channel of the required width 
 and depth is by itself a very difficult problem in such 
 a powerful stream as the San Juan. 
 
 Nature does not like a regular depth and width in 
 the bed of a great river ; it is contrary to its laws. In 
 curves the river fills up the concave side of its bed and 
 digs the convex side, and when it changes its curva- 
 ture from one side to the other, the river expands and 
 fills up its channel to get an intermediary state for 
 passing from the deep channel on one side to the deep 
 channel on the other side. 
 
 This any great river will do constantly with the 
 proper elements of its bed without borrowing any 
 foreign material, and the problem, even without any
 
 intervention of sediments from lateral tributaries, is a 
 difficult one to solve. The difficulty can, of course, 
 easily go over the boundaries of human practicability 
 when the question becomes complicated with that of 
 great masses of sediment brought into the bed. 
 
 Curves. — To examine this very important subject 
 of curvature, the most essential of all for safe navig^a- 
 tion, we have not yet the definitive plan of the Isthmian 
 Canal Commission, for the Nicaragua Canal, but as 
 this Commission has adopted in its essential lines the 
 Nicaragua Canal Commission's project, and as curva- 
 ture is commanded nearly absolutely by the natural 
 disposition of the ground, one may take, as a fair 
 approximation, the curvature of the Nicaragua Canal 
 Commission's route as the one that will be more or 
 less presented by the definitive project. Leaving 
 aside the curves in harbors, or at the entrance of the 
 locks, where the ships have a very reduced velocity, 
 we find that the Panama route has 23 curves of a 
 totalized length of 19.5 miles, and that the Nicaragua 
 route has 82 curves of a totalized length of 53.5 miles. 
 
 It is not enough to state the number of curves ; it is 
 much more important to state their radii. All the 
 curves of the Panama canal are of 10,000 feet radius 
 or more, with the exception of three, which have 
 8200 feet radius. There are, on the contrary, 69 
 curves in the Nicaragua Canal below 8000 feet, of 
 which 50 are between 3000 and 4000 feet radius. 
 
 But it is not only the number of curves and their 
 radii which has to be considered, but also whether 
 they are located in places where water will be still or 
 not. 
 
 In Panama there are only three curves of 10,000 
 feet radius where the Canal and the Chagres will be in
 
 the same location, that is to say, where eventually 
 currents may take place. In Nicaragua we find 58 
 curves, having a total extension of 37 miles, where 
 the Canal will be located in the San Juan River itself, 
 and of those 58 curves, 43 are between 3000 and 
 4000 feet radius, and have a total extension of 26 
 miles. 
 
 It must be borne in mind, that in that part of the 
 Canal there will be nearly 28 miles excavated into 
 the bottom of the river to a depth of 16 feet for 
 the larger part. The maintenance of that channel 
 opened into silt and sand seems (from my personal 
 point of view) to be extremely difficult, and will neces- 
 sitate constant dredging in a river carrying in floods 
 100,000 cubic feet of water, that is to say, one quar- 
 ter of the amount in the Niaorara Falls. 
 
 It is obvious that ships will meet there an accumu- 
 lation of extreme difficulties, sharp curves, heavy river 
 currents, constant heavy gales and impediments either 
 from the dredges themselves, or from the sand and 
 silt they will have to remove. 
 
 Who could guarantee that those combined diffi- 
 culties when brought to the extremes simultaneously 
 would not stop sometimes, even if not often, all 
 transit ? 
 
 In Panama, the large and easy curves, the absence 
 of winds, the scarcity of river currents, and the rarity 
 of floods, give quite a reverse impression as to the 
 eventual facilities offered to ships. 
 
 Harbors. — With regard to harbors, the advantage, 
 as every one admits, is with Panama, both of whose 
 terminals have excellent harbors. The Nicaragua 
 Atlantic terminal is very bad. The immense quantity 
 of sand thrown into the sea by the San Juan, whose
 
 mouth lies south of Greytown, is maintained in sus- 
 pension by the continuous agitation due to the con- 
 stant easterly trade winds, and brought into Greytown 
 by a continuous northern stream of sand. The Grey- 
 town harbor, which, fifty years ago, was a good one, 
 is now virtually closed by the constant accretion of 
 the sand, and the maintenance of the entrance to the 
 Canal there would be very difficult. 
 
 If it is understood by the designation of harbors, 
 those points of the route where canal navigation is 
 changed for a navigation into an immense body of 
 water beaten by storms, and liable to give great 
 waves, one is entitled to say that the Nicaragua route, 
 outside of its ocean harbors, has two others in the 
 Lake of Nicaragua, 
 
 This lake is a real sea, about as large as the sea of 
 Marmara. 
 
 The violent gales that continually blow over it, 
 with sudden changes of direction due to the reflection 
 of the currents of air on the mountains, make this 
 interior sea always agitated. Its violent storms are 
 quite characteristic and well known. 
 
 An inferior current brings to the southeastern side 
 all the light sediment thrown into the lake by its 
 tributaries, and this sediment accumulates in the 
 region where the outlet of the lake, the San Juan, is 
 located. 
 
 An artificial channel twenty-two miles long has to 
 be dug in that mass of mud, and this channel forms, 
 so to say, the harbor approach on the east side of the 
 interior sea. Close to the point where this channel 
 leaves the shore, a great torrential tributary of the 
 lake, carrying a considerable mass of sediment, 
 brought from the volcanic ridgfe of Costa Rica, falls 
 
 23
 
 into the lake : it is the Rio Frio, which will not add 
 to the facility of maintaining the channel depth. 
 
 To judge at the same time the extraordinary diffi- 
 culty of that maintenance and the danger to which 
 transitting ships will be exposed in that harbor ap- 
 proach, one must forget the name of lake, which con- 
 veys the erroneous idea of still, sleeping water, and 
 think what an unprecedented enterprise it would be 
 to make an harbor approach in the ocean consist- 
 ing of an artificial channel, twenty-two miles long, 
 opened into mud or silt, and constantly exposed to 
 be brutally filled up by the sweeping waves at every 
 storm. 
 
 Such a point of view would be in the actual case 
 much nearer to reality, than the conception of a 
 channel opened into the bottom of a Swiss lake. 
 
 Building Expenses and Time of Transit. — The 
 exceptional advantages which characterize the Panama 
 route compared to the Nicaragua route are in no 
 way counterbalanced by larger building expenses. 
 According to the estimates of the Isthmian Canal 
 Commission, the completion of the Panama Canal 
 will cost 58,000,000 dollars less than the construction 
 of the Nicaragua route, which is estimated at 200,- 
 000,000 dollars. It is obvious that the estimation of 
 the cost of completing such a work, where already ^'],- 
 000,000 cubic yards have been excavated, in all parts 
 of the Isthmus and in all conditions of work, enjoys 
 a far higher degree of certainty than an estimate 
 made on a line where no works have been executed * ; 
 
 * The Isthmian Canal Commission states that the only excavation executed 
 on the Nicaragua Isthmus consists of a channel between 150 and 230 feet 
 wide, 16 feet deep and three quarters of a mile long. This insignificant work 
 made in the Greytown swamps represents a cube inferior to one three hun- 
 dredth part of the total volume of the prism of the Nicaragua Canal.
 
 on the other hand it is a matter of common experience 
 that whatever be the care with which surveys, sound- 
 ings, and plans are made, the unforeseen circumstances 
 which are met in a new ground do not modify the 
 previsions towards reduction of expenses but towards 
 increase. 
 
 The time of transit is estimated by the Isthmian 
 Canal Commission, at twelve hours for Panama and 
 thirty-three for Nicaragua. If one remembers the 
 length of the two routes, and the number of locks, it is 
 evident that this calculation must have been based 
 upon the hypothesis that ships will go at the same 
 speed in both cases, and that no allowance was made 
 for the difficulties to be met on the Nicaragua route. 
 
 This shows that the advantage of distance over 
 Nicaragua, between both sides of North America, is 
 practically erased by time of transit. 
 
 PART II 
 
 Stability. — I propose now to touch upon another 
 point which does not concern the construction proper 
 of the Canal, but has reference to future contingen- 
 cies, and which was not discussed by the United 
 States Isthmian Canal Commission in its preliminary 
 report. 
 
 I wish to speak of a danger arising from seismic 
 disturbances, both during construction and after. 
 
 In Panama, there is within a distance of one hun- 
 dred and eighty miles from the Canal no volcano, 
 even extinct. The Isthmus there, since its formation 
 in the early quarternary period, before man appeared 
 on the earth, has not been modified. 
 
 This is quite the contrary in Nicaragua, which has 
 been always the site of seismic convulsions, whose 
 
 25
 
 lake was formerly a gulf of the Pacific Ocean, and 
 whose name was associated with the most terrible 
 volcanic explosion ever recorded in history before 
 the Krakatoa explosion in Sound's Islands. 
 
 The explosion of the volcano Coseguina in 1835 
 lasted 44 hours, the noise was heard at a distance of 
 1000 miles, the ashes were brought 1400 sea miles 
 by the winds, the mass ejected into the air was 
 calculated to have covered a surface equivalent to 
 eight times the surface of France, and the volume 
 was calculated to be equal to 50 cubes having sides 
 of 1 100 yards, which allows me to say that during 
 these 44 hours the volcano ejected every six 7iiinutes 
 a volume of stone and ashes eqiml to the total volume 
 of the prism of the Nicaragua Canal, as it was calcu- 
 lated by the Nicaragua Canal Commission, and which 
 will necessitate eight years of excavation. 
 
 In the very centre of Lake Nicaragua is a volcano 
 in constant activity, the Omotepe, whose last great 
 eruption occurred in 1883. 
 
 Between the two above named volcanoes we find 
 a series of volcanoes in recent or continuous activity, 
 the Hell of Masaya, on the shore of Lake Nicaragua, 
 the celebrated Momotombo, on the shore of Lake 
 Managua, the volcano of the Pilas, which was born in 
 1850, the Santa Clara, the Zelica, the Nindiri, being 
 the best known of them. 
 
 The continuity of volcanic disturbances is stated 
 in an appendix to the Nicaragua Canal Commission's 
 report : "In the northwestern part of Nicaragua 
 slight earthquakes are frequent. Scarcely a mouth 
 passes without one or more being noticed. The centre 
 of these disturbances is always near the line of the 
 Nicaragua volcanoes ; the line of volcanoes begins luith 
 
 26
 
 Madeira (near the Omotepe), at the southern end, in 
 Lake Nicaragua, and terminates at Coseguina, at the 
 northern end, near the gulf of Fonseca." 
 
 Two most important facts have been recently estab- 
 lished by Mr, Bertrand, foremost geologist and 
 member of the Institute of France. 
 
 (i) The Lake Nicaragua is one of the three lines 
 of least resistance in Central America, which are a 
 site of election for great seismic disturbances. It is 
 the line of depression between the Costa Rican volca- 
 noes and the Nicaraguan, and plays the same part as 
 the other two : the bay of Fonseca, which is a vol- 
 canic lake characterizing the depression between the 
 Nicaraguan and Salvadorian volcanoes, and the Lake 
 Pacayan, characterizing the depression between the 
 Salvadorian and Guatemalan volcanoes. These two 
 last lines of least resistance have been the site of 
 the most terrible convulsions owed to the Cose- 
 guina for the former, and to the Fuego (Fire) for the 
 latter. 
 
 (2) The underground fire is going south, and in- 
 creasing i7t Nicaragua. From the figures given by 
 Mr. Bertrand I calculated that before the nineteenth 
 century, out of all the great explosions or earthquakes 
 recorded, 45^ belonged to Guatemala, 35^ to Salva- 
 dor, and 20;^ to Nicaragua, whereas in the nineteenth 
 century, only 30^ belonged to Guatemala, 45^ to Sal- 
 vador, and 25^ to Nicaragua, showing an evident ten- 
 dency to a displacement of the activity southward 
 and an increase in Nicaragua. 
 
 To justify these figures one can say that several 
 volcanoes became extinct in Guatemala, and that 
 none was extinct in Salvador nor in Nicaragua, but, 
 on the contrary, that two were born in Salvador, 
 
 27
 
 Izalco, in 1770, and Ilopango, in 1880, and one was 
 born in Nicaragua, that of Las Pilas, in 1850. 
 
 Danger for Construction. — The continual earth- 
 quakes may have a fatal influence on the definitive 
 transformation from half-liquid mud into hard stone, 
 of the concrete, which will during eight years be con- 
 tinually poured in the great Boca San Carlos dam ; 
 these violent shocks, interfering every month or more 
 with the gradual crystallization of the elements of 
 concrete, may destroy their reciprocal adherence, and 
 ruin the perfect homogeneity of the solid mass which 
 is imperatively necessary for the part it has to play. 
 
 Danger for the Canal once Built. — It is en- 
 tirely false to compare the equilibrium of dams and 
 locks with that of a high tower or of a church. A 
 wall or tower even fissurated can stand after an earth- 
 quake. A longitudinal fissure in a dam, which will 
 not alter its equilibrium as a wall without pressure of 
 water, would mean its immediate overthrow when the 
 water pressure is exerting its force upon the surface 
 of the inside fissure. 
 
 Outside of the impending and terrible danger of 
 seeing ruined the dam or the locks by a great seismic 
 commotion, one must not forget that there is great 
 probability of seeing formed in the sea of Nicaragua, 
 which is 100 miles long and 45 miles wide, one of 
 those terrible tidal waves which were so destructive 
 in Lisbon (earthquake of 1752), and Krakatoa, 1883, 
 the latter being 100 feet high and the former 40, and 
 which caused unlimited disaster. 
 
 It must be borne in mind that these terrible 
 menaces would mean, if realized, not only the de- 
 struction of that costly Canal, but the ruin of the 
 immense interests of both sides of America, which
 
 will have been developed by the great waterway and 
 receive a death blow by its paralyzation. 
 
 Transformation of the Panama Canal into a 
 BosPHORUS. — Nothing similar can be feared in Pan- 
 ama, as no trace of any local volcanic activity may be 
 found on that Isthmus, whose rare and small seismic 
 vibrations come from distant centres. 
 
 The future, on the contrary, far from being open 
 for destruction, is open for a gradual transformation 
 from a lock canal into a level canal, into a Bospho- 
 rus, which means a rapid transit in five hours from 
 ocean to ocean. This can be done without stopping 
 or troubling the navigation even for a quarter of an 
 hour, by following the solution I have given years 
 ago to this question, which is extremely simple, and 
 consists, all engineers will understand me, in making 
 the two gates of a lock of the same height. 
 
 CONCLUSION 
 
 The facts that I have related demonstrate the fol- 
 lowing statements : 
 
 I. It is very questionable whether the continuous 
 earthquakes will allow the construction, on the Nica- 
 ragua route, with all its indispensable qualities, of a 
 substantial masonry dam, which is the key of the 
 whole Canal. 
 
 29
 
 II. Admitting a dam could be built, the Nicaragua 
 route, whatever may be the engineering skill displayed 
 and the expenses made, will never acquire the two 
 most essential qualities necessary to an interoceanic 
 canal, — continuity of operatioji and security of transit. 
 
 The large ocean steamers will have there to strug- 
 gle, deprived of any means of resistance,* against the 
 combined efforts of the continuous violent eales, of 
 the heavy river currents, of the impediments resulting, 
 of the constant modifications of the depths in the 
 channel, and of the presence of the numerous dredges 
 that will have to keep the way open, and this when 
 they will be steering with great difficulty around an 
 extraordinary number of curves, the short radii of 
 which ought to be, in themselves, considered as in- 
 compatible with the navigation of big ocean ships in 
 a narrow channel. 
 
 The ships will also have to meet two bad, exposed, 
 and dangerous passages, when going from the Atlantic 
 into the Canal and from the Canal into the Lake of 
 Nicaragua. 
 
 One is allowed to say that continuity of transit and 
 safety of navigation will be constantly at the mercy of 
 conflicting elements and beyond the control and prevision 
 of man. 
 
 III. If the experience of four centuries is not a mere 
 word, if the undisputable proofs, written in letters 
 
 * It is a fact well known to naval men, that a big ship floating in shallow 
 water is partially deprived of its steering faculty. The reaction of inferior cur- 
 rents on the rudder disables it to a certain extent, and its action is uncertain 
 and irregular. 
 
 The accident suffered by the battleship Massachusetts, that got aground go- 
 ing out of Pensacola on the 2ist March when this pamphlet was in course of 
 printing, is a good illustration of this disability of steering in shallow water.
 
 of tire on the surface of the soil,* of the continuous 
 violent and increasing volcanic activity in Nicaragua, 
 are not a mere clream, the route over that Isthmus is 
 not only eventually exposed to, but certain, sooner or 
 later, to be the prey of, that uncontrollable power of 
 nature before which flight is the only resource. 
 
 If one thinks that not only the enormous cost of 
 such a waterway would be at stake but also the very 
 basis of the prosperity, the wealth of the millions of 
 people who will settle on the west coast of North 
 America, as soon as the construction of the Canal will 
 join them with the other side of the continent and 
 with Europe, one hesitates to calculate the conse- 
 quences that would result from one of those seismic 
 convulsions, which most probably will be still more 
 terrible in the future than they have been in the past 
 on that part of the Isthmus. 
 
 To prefer definitively the Nicaragua route to the 
 Panama route, the unstable route to the stable one, 
 would mean to prefer the stability of a pyramid on 
 its point to the stability of a pyramid on its base when 
 to that stability is attached the prosperity and welfare 
 of a whole continent. 
 
 IV. The Panama route, having no winds, no cur- 
 rents (except on rare occasions), no sharp curves, no 
 sediments, no bad harbors, no volcanoes, enjoys to the 
 highest degree the three essential qualities totally want- 
 ing for the Nicaragua solution, — continuity of opcra- 
 
 *To the people who think I am exaggerating this capital point I will say. 
 Open any dictionary of geography, any encyclopedia, and read the article titled 
 " Nicaragua." I will say also: look atthe coat of arms of the Republic of Nica- 
 ragua, look at the Nicaraguan postage stamps. Young nations like to put on 
 their coat of arms what best symbolizes their moral domain or characterizes their 
 soil. What have the Nicaraguans chosen to characterize their country on their 
 coat of arms, on their postage stamps ? Volcanoes ! 
 
 31
 
 Hon, security of transit, stability of structure.* Outside 
 of that it is three times shorter, will cost much less 
 than the Nicaragua route and is easily transformable 
 into a Bosphorus, the only form that will definitely 
 answer to the world-wide interests to be served by 
 the route, and allow of a passage from ocean to ocean 
 in five hours. 
 
 * The superior qualities of the Panama route, from the point of view of safe 
 and continuous operation, are such that it can be fairly asserted that, assuming 
 the two canals were built and that of Nicaragua freed of any tolls, ships would, 
 in the intermittent periods of navigability of the Nicaragua Canal, still prefer the 
 Panama route, as the tolls of this Canal would certainly be less than the insur- 
 ance fees to be paid to pass over the unsafe route of Nicaragua. 
 
 32
 
 NICARAGUA OR PANAMA. P. BUNAU-VARILLA. 
 
 RESPECTIVE LENGTHS OF CANAL NAV- 
 IGATION OVER THE NICARAGUA 
 AND PANAMA ROUTES. 
 
 NICARAGUA ROUTE 
 
 This plate, drawn at the same scale of one inch per 
 twelve miles, gives the relative lengths of canal navi- 
 gation in both routes, according to the figures of the 
 Isthmian Canal Commission's Report, being under- 
 stood by canal navigation all the parts of the way 
 where ships will have to follow an artificial channel, 
 whether dug in open land or below the bed of a 
 river or below the bottom of a lake, and without 
 taking into account the part of the way where ships 
 will float in free deep water. Canal navigation will 
 be 120.53 miles in Nicaragua, and 38 miles in 
 Panama, to which must be added 66 miles in Nica- 
 ragua, and seven miles in Panama, for deep-water 
 navigation. 
 
 PANAMA ROUTE 
 
 I
 
 NICARAGUA OR PANAMA, P. BUNAU-VARILLA. 
 
 RESPECTIVE DEPTHS OF GREAT CUTS 
 ON THE NICARAGUA AND PANAMA 
 ROUTES. 
 
 This plate gives, drawn at the same scale of one 
 inch for sixty feet, the respective depths of great 
 cuts that are to be dug on both routes. 
 
 On the Nicaragua route, according to the figures 
 of the Isthmian Canal Commission, the greatest cut 
 is at Tamborcito, and is 297 feet deep. 
 
 On the Panama route the Culebra ground, origi- 
 nally 274 feet above the bottom of the Culebra cut, 
 according to the project adopted by above named 
 Commission, is to-day reduced to no feet, owing to 
 the works executed by the old and the new Panama 
 Company. 
 
 NICARAGUA ROUTE 
 
 PANAMA ROUTE
 
 
 iri 
 cl 
 
 C 
 
 rs 
 
 w 
 
 rf 
 
 w 
 
 tl 
 c 
 c 
 
 is 2 
 
 a 
 
 h 
 
 I 
 
 a 
 
 tl. 
 
 N 
 
 RiVEH 
 
 NAL BETWEEN 
 '>UA8tPA<:iFtC 
 
 L>L> 
 
 ^ 
 
 
 at 
 in 
 tl
 
 Tint pUlc jfives ihc suKWiiv 
 by innuiting ship* on the Nica 
 
 urvea in hvbon or ai 
 
 diannd hu U be opened lot a loial length of }j.gf> mil 
 bn) (Tor the lugcr part). Ii mu^i U bom.- in mimi it 
 
 dhatge in\ fram July 
 nwmum bring 45.500 
 
 the nine locuicm. Ouuide ol 
 
 
 b only 4800 eubiefct a mond from July lo Dwcmbcr; 
 ud the ptMi euqitionit floodi (four in c«iniy«nc yean) 
 
 ■Us, j(mo in i8Sg, 18.000 in 1896, and 41,000 cubic fen 
 
 
 N I CARA GU A 
 
 
 LiUL;'Ui> 
 
 iii!i[?[>iLi[^biiL>C>[>l>l!iQ[>i[>i>C?UL>'L?[^ Pbli 
 
 R OUTE 
 
 D'D'LsD'bb.C/'llliD'D' DLi[>L>L^ L> [> L^C>LiL^i>[>C?Li[>L>D 
 
 ■l:.-^L> ili 
 
 PANAMA ROUTE 
 
 
 N, !\ K N 
 
 n h i'\ i \ i\
 
 NICARAGU/ 
 
 RELATk tN THE PERiOO 
 SEI ^^'^^^^^ 
 
 TH 
 
 GU 
 
 NIG ^"-- 
 
 From 
 
 member \ 
 
 number oj 
 
 violent e^y-y^ /^ TH£ 
 theninetK?^,7y/r 
 
 A 
 
 the three 
 ica, Guat 
 culated tl 
 century 4 
 and 20^ 
 figures fc 
 tury 30^ 
 for Nicar 
 towards 
 tivity, as 
 curves, w 
 intensity 
 canoes fr 
 
 JdQ5 
 
 \^ 
 
 
 < 
 o 
 a:
 
 NICARAGUA OR PANAMA. P. BUNAU-VARILLA. 
 
 RELATIVE FREQUENCY OF GREAT 
 SEISMIC DISTURBANCES IN THE 
 THREE VOLCANIC GROUPS OF 
 GUATEMALA, SALVADOR, AND 
 NICARAGUA. 
 
 From the statistics produced by Mr. Bertrand, 
 member of the Institute of France, in relation to the 
 number of great volcanic explosions or e.xceptionally 
 violent earthquakes recorded before the beginning of 
 the nineteenth century and from that time to 1885, in 
 the three powerful volcanic groups of Central Amer- 
 ica, Guatemala, Salvador, and Nicaragua, I have cal- 
 culated that before the beginning of the nineteenth 
 century 45 % belonged to Guatemala, 35 % to Salvador, 
 and 2ofo to Nicaragua ; and that the corresponding 
 figures for same groups were in the nineteenth cen- 
 tury 30^ for Guatemala, 45;^ for Salvador, and 25^ 
 for Nicaragua, which demonstrates a displacement 
 towards Nicaragua of the maximum of seismic ac- 
 tivity, as is shown by comparing the two dotted 
 curves, which can be considered as representing the 
 intensity of volcanic activity along the line of vol- 
 canoes from North Guatemala to South Nicaragua. 
 
 ftCLATIVE SEISMIC ACTIVITY IN THE PERIQO 
 ANTERIOR TO THE /9" CENTURY 
 
 RELATIVE SEJSMIC ACTIVITY IN THE 
 PERIOD OETIVEEN BECINNINC OF THE 
 ISV CENTUfJY AND /885 

 
 ■I^C SOUTHERr, qr,-. 
 
 A 000 547 955 
 
 ^
 
 f '^''^' 
 
 ■V 
 
 • 
 
 If 
 
 m 
 
 
 
 m 
 
 i^ • 
 
 *? 
 
 ^ 
 
 
 •Jf 
 
 ^- 
 
 Sv"o