370 



SCIENCE. 



[N. S. Vol. XIX. No. 479. 



usual, well filled with several papers which 

 had been left over from Tuesday, and with 

 the remaining papers of the program. One 

 of these was by Professor Frank B. Will- 

 iams, of Union College, Schenectady, N. 

 Y., on 'Methods of Determining the Coeffi- 

 cients of Elasticity.' By loading a beam 

 supported at its ends at two points equi- 

 distant from each other and from the 

 ends, and thereby eliminating the cross 

 shear, the coefficient of linear elasticity can 

 be determined by measuring the deflections. 

 Knowing E, the coefficient of elasticity for 

 shearing is obtained by the formula given 

 by Professor Merriman. 



General E. W. Serrell, of West New 

 Brighton, N. Y., followed with a paper on 

 'A Proposed Method of Building the Man- 

 dingo Ship Tunnel,' through the Cordil- 

 lerian range of mountains in Central Amer- 

 ica, where the distance from sea to sea is 

 but twenty-nine and one half miles. The 

 Gulf of San Bias and the magnificent har- 

 bor of Mandingo are at the north end, while 

 directly south, behind the Pearl Islands, 

 within the Bay of Panama, is another 

 harbor. The mountain range averages 

 aboiit 1,520 feet high. The proposed ship 

 tunnel is to have portals 300 feet high. 

 The length of the crown of the tunnel will 

 be less than five miles. Instead of the 

 shales found in the lines of the two other 

 proposed routes for ship canals across the 

 isthmus, the geological formation at this 

 point has been investigated by an expert 

 geologist, who states that the rock extends 

 across the isthmus, that it is very uniform, 

 strong and in every way suited for tunnel- 

 ing. Tested at the Watertown Arsenal, 

 it was found to be stronger than Quiney 

 granite. Analyzed at the geological labora- 

 tory at Washington, it was found that 

 hornblende predominated in the granite. 

 The canal-tunnel will be a straight line 

 from sea to sea, and therefore capable of 

 passing a ship of any length. The paper 



discussed the elements of the cross-section 

 of the tunnel, the method for its construc- 

 tion, using three headings and understoped 

 as well as open benches, and nine overhead 

 tracks to remove the debris, and it is stated 

 that the 18,000,000 cubic yards in the tun- 

 nel and the 37,000,000 cubic yards of ex- 

 cavation outside the tunnel can all be made 

 for less than $100,000,000. It is estimated 

 that the work can be completed in two 

 years, although three years have been al- 

 lowed. 



Considering its good geological position, 

 the excellence of the harbors available, the 

 abundant supply of water at sea-level, no 

 locks to delay passage of shipping, and 

 more than ten times the capacity for busi- 

 ness, as compared with any other proposed 

 isthmian canal, it would be cheap at three 

 or four times the cost, to say nothing of 

 the short time which will be required to 

 build it. 



Before adjourning on Thursday to enjoy 

 the hospitality of the officers of the World 's 

 Fair, the section had the privilege of listen- 

 ing to Lieutenant G. L. Garden, U. S. Rev- 

 enue Cutter Service, on 'Some Topics Con- 

 nected with the Machinery Department of 

 the World's Fair.' The author is superin- 

 tendent of 'arsenal tools' in the depart- 

 ment of machinery at the fair, and was 

 sent abroad and secured many of the for- 

 eign exhibits of machinery. 



The section chose Professor David S. 

 Jacobus, of Stevens Institute, Hoboken, N. 

 J., as its vice-president for the nest meet- 

 ing; and, on nomination to the general 

 committee, he was duly elected. 



To say the least, the program of Section 

 D was very full. A large number of the 

 papers were by the leading experts of the 

 country on the subjects discussed. It is 

 questionable whether the interests of sci- 

 ence are the better advanced by permitting 

 a more lengthy and general discussion of 

 the papers presented, than by having the 



