INDUSTRIAL PllOGKESS DURING THE YEAR 187G. ccxix 



spring water only. The borings in question have demonstrated, 

 quite independently of the shore sections, the character and thick- 

 ness of the stratum through which it is proposed to pierce the tun- 

 nel ; and, further, that, notwithstanding the fact that the thicknesses 

 of the several strata all diminish toward the French coast, they are 

 yet of sufficient magnitude for all the engineering requirements of 

 the contemplated improvement. 



All the knowledge gained by this means, however, although it 

 may meet the most favorable expectations of the friends of the tun- 

 nel, neither proves nor disproves the hostile theories which have 

 long existed, and which still exist as to the occurrence of a verti- 

 cal fissure along the whole median line of the English Channel, 

 and which discussion will only be settled when the driftways of 

 the tunnel itself are actually driven from the shores of both 

 countries, and are about to meet midway under the bottom of the 

 sea. 



It may be well to add, in conclusion of this subject, that, should 

 the plan of directly driving a tunnel be found imiDracticable, there 

 remain several other plans of connecting France and England: one 

 by a colossal bridge ; another by a subaqueous tube laid on the bed 

 of the channel; and a third, consisting of a platform supported on 

 wheels, which run on rails laid on a causeway of some thirty-three 

 feet in height, and thirteen feet in width, raised on the comparatively 

 level bed of the channel. On this causeway it is proposed to run a 

 vehicle 330 feet in length, 125 feet high, and composed of a pontoon 

 at the base, and a platform above the water, united by suitable fram- 

 ing. The platform is to be large enough to take on board an entire 

 railway train ; and the device is to be propelled by an engine located 

 on the platform, which, by means of a chain-belt, operates a drum, 

 over which winds a chain that lies upon the causeway. This plan 

 is an extension of the ideas embodied in M, Leroyer's water railway, 

 in successful operation at St. Malo, in France. 



Concerning the project of an interoceanic canal across the Amer- 

 ican isthmus, of which we gave a somewhat detailed account in our 

 Record of last year, it may be remarked that, although our govern- 

 ment has taken no steps toward carrying out the views of the com- 

 mission which recommended the Nicaragua route, the subject of 

 the canal has attracted considerable attention abroad. It was an- 

 nounced, for example, at a late session of the Soci6t^ de Geographic, 

 that a considerable body of gentlemen had obtained a concession 

 from the Colombian government for the building of an interoceanic 

 canal across the Darien Isthmus. A scientific commission, it was 

 affirmed, would start in November to make a thorough survey of the 

 proposed line between the Gulfs of Uboba and St. Miguel. It is 

 furthermore affirmed that the Colombian government, at the insti- 

 gation of M. Gogorza, has authorized the survey of a route by way 



