4o6 



SCIENCE. 



[Vol. XIII. No. 329 



the time of his arrival at Kong, — a period of six months and a 

 half, — he must have traversed from seven hundred to a thousand 

 miles. Judging from this fact, it would take him at least a year to 

 complete his proposed tour from the city of Kong, and his return 

 to the same. We must not be surprised at not having heard from 

 him : that may be due to a lack of opportunity for sending mes- 

 sages. 



Having given this description of the journey of Capt. Binger, we 

 can but wish that it may terminate as well as it has begun. 



GUST AVE EIFFEL. 



Before proceeding to speak of the Eiffel Tower in detail, 

 Engineermg, in its issue of May 3, in which is a noteworthy survey 

 of the opening Paris Exhibition, takes occasion to say a few words 

 about Gustave Eiffel and his works. Born at Dijon in 1832, he 

 passed brilliantly through the Ecole Centrale, and commenced the 

 active pursuit of his profession in 1855. One of his first works 

 was the completion of the foundations of the great railway-bridge 

 of Bordeaux by means of compressed air, — a system then but little 

 known in France. After this work, M. Eiffel constructed a large 

 bridge over the Nive at Bayonne, and two others at Capdenac and 

 at Florae. 



In 1867 he was intrusted by M. Krantz, the commissioner-gen- 

 eral of the Paris Exhibition of that year, with the task of checking 

 experimentally the calculations made for the large buildings. In 

 1868 he constructed, under the direction of M. de Nordling, 

 engineer of the Orleans Company, the viaducts with iron piers, 

 upon the line between Commentry and Gannat. It was in these 

 viaducts that he first employed the system consistently followed by 

 him afterwards, of wrought-iron braced structures, instead of cast- 

 iron columns or masonry piers. A little later he introduced, with 

 great success, a system of launching bridges from their site of 

 erection on the ground across the piers previously built to receive 

 them. His first attempt in this direction was in 1869, with the 

 Sioule viaducts, followed by another at Vianna, in Portugal, where 

 iron girders more than 1,800 feet in length were launched into 

 position. Then came the viaduct of Tardes, near Montlugon, 

 which was launched at a height of 328 feet above the ground, over 

 piers 340 feet apart. 



M. Eiffel was the first among French engineers to employ the 

 system of erecting bridges of great span without scaffolding, by 

 building out the structure piece by piece. His first work of this 

 class was at Cubzac, near Bordeaux, where he crossed a river with 

 a bridge 236 feet span without any staging. At Tan-an, in Cochin 

 China, he erected in a similar way a bridge of 262 feet span. Of 

 arched bridges built in the same manner, the most important, until 

 it was surpassed by the viaduct of Garabit, was the great bridge 

 over the Douro, at Oporto, the central span of which is 534 feet, 

 and the rise of arch 13S feet, the height of rails above tfie water- 

 level being no less than 200 feet. But he surpassed himself in the 

 Garabit viaduct, where an arch 541 feet span crosses the torrent of 

 the Truy^re 400 feet above it. Among the other great engineer- 

 ing works carried out by M. Eiffel must be mentioned the Pesth 

 railway-station ; the Szegedin bridge ; the principal fagade of the 

 Paris Exhibition of 1878; and the dome of the Observatory at 

 Nice, 75 feet in diameter, and weighing more than 100 tons, which 

 floats within a circular trough, so that the effort required to move 

 it is almost inappreciable. Scarcely less remarkable as an engi- 

 neering work, and as a triumph of the founder's art, is the gigantic 

 statue of Liberty, modelled by Bartholdi, and presented by France 

 to the United States, where it now stands lighting the entrance to 

 the harbor of New York. 



The great series of locks which were to have formed a sort of 

 giant staircase for the passage of ships across the Isthmus of 

 Panama was elaborated as to design, and considerably advanced 

 as to execution, when the great work collapsed. From the fore- 

 going rapid sketch, it will be seen that few engineering construct- 

 ors have carried out so many important and original works as M. 

 Eiffel ; and the success which has uniformly attended him was a 

 guaranty for the stability and beauty of his latest effort, the Column 

 of the Republic, and his own monument. 



Of course, the idea of a tower of gigantic height is not a new 



one. Not to mention the efforts of the early engineers which had 

 the unexpected result of inventing foreign languages, there are 

 three better authenticated and more recent proposals than the in- 

 stance in which the sons of men said, " Go to, let us build us a 

 tower whose top may reach unto heaven, and let us make us a 

 name." The earliest was that of the splendid but eccentric genius 

 Trevithick in 1S33; then came the proposal of the well-known 

 American engineers, Messrs. Clarke & Reeves, who offered to con- 

 struct for the Philadelphia Exhibition, in 1876, a tower, 1,000 feet 

 in height, of wrought iron, and about 150 feet in diameter at the 

 base. Finally, in iSSi, a M. Sebillot proposed to light Paris elec- 

 trically by a 1,000-foot tower. 



Excepting the American project, none of these scTiemes had any 

 practical value, but the proposal of Trevithick is worth referring to 

 here. He suggested, in a letter published in the iMormng Herald 

 of July II, 1832, that the passing of the Reform Bill should be 

 commemorated by a gigantic tower made of cast iron, 1,000 feet 

 in height, 100 feet in diameter at the base, and 12 feet in diameter 

 at the top. It was to be set upon a stone plinth 60 feet high, and 

 was to have a capital 50 feet in diameter, supporting a colossal 

 statue. The shape was to be that of a cone, and an internal 

 cylinder 10 feet in diameter was to run from the ground to the top 

 of the structure. Trevithick proposed that the tower should be 

 composed of 1,500 symmetrical segments, with internal flanges 

 around their edges for bolting them together. Each segment was 

 to be pierced with a large circular opening for lessening the weight 

 and reducing the wind-pressure. The total weight was to be 

 about 6,000 tons, and each of the cast-iron panels was to weigh 

 about 3 tons. The contract price offered for the castings was £j 

 per ton, the total estimate of expense was under ^80,000, and 

 Trevithick undertook the erection of the column in a period not to- 

 exceed six months. Passengers were to be raised to the top of the 

 tower in the central cylinder, which was to be fitted with a piston 

 providing accommodation on its upper surface for twenty-five per- 

 sons ; and the piston was to be raised from the bottom to the top- 

 by compressed air forced into the cylinder, and controlled by suit- 

 able valves. Fortunately for the memory of Trevithick, this scheme 

 remained upon paper. 



The Eiffel Tower is the natural development of the class of 

 work upon which its constructor has been occupied for so many 

 years. It was the direct outcome of a series of investigations- 

 undertaken by M. Eiffel in 1S85, with a view of ascertaining the 

 extreme limits to which the metallic piers of viaducts could be 

 pushed with safety, this special line of investigation having refer- 

 ence to a proposed bridge with piers 400 feet in height and 140 feet 

 of base. The idea of the great tower followed, preliminary plans 

 were prepared, and calculations made by two of M. Eiffel's princi- 

 pal engineers, — MM. Nouguier and Koechlin, — and by M. Sauves- 

 tre, architect. Naturally, the leading principle followed was that 

 adopted by M. Eiffel in all his lofty structures ; namely, to give to- 

 the angles of the tower suclka curve that it should be capable of 

 resisting the transverse effects of wind-pressures, without neces- 

 sitating the connection of the members forming these angles, by- 

 diagonal bracing. The Eiffel Tower, therefore, consists essentially 

 of a pyramid composed of four great curved columns, independent 

 of each other, and connected together only by belts of girders at 

 the different stories, until the columns unite towards the top of the 

 tower, where they are connected by ordinary bracing. Iron, and 

 not steel, was used in the construction throughout. 



MENTAL SCIENCE. 



Psychic Cures. 



Our first record of the practitioners of the healing art describes 

 them as invested with the priestly function, thus making the cure 

 of physical ills a result of intellectual and religious influence. 

 When reading the records of the past in the light of modern 

 knowledge, we can trace almost at every point the very marked in- 

 fluence of mental states in the cure, sometimes described as mirac- 

 ulous, of disease. The repute of drugs altogether harmless, or of 

 the physician who gave the drug, is often due to the successful ac- 

 tion of the patient's own belief upon his susceptible system. And 

 quite as truly are the wonderful cases of the infliction of ills by 



