12 



SCIENCE, 



[Vol. IV., No. 74. 



cial train, courteously tendered by the management 

 of the New York, West-Shore, and Buffalo railroad, 

 left New York on the morning of June 9, carrying 

 a large number of members from the eastern states, 

 while many more came from other directions ; the 

 total number present, including guests, being be- 

 tween three and four hundred. At the opening 

 meeting, on Tuesday, June 10, the reading of papers 

 was begun ; and many of great interest were pre- 

 sented at this and the following sessions. Mr. 

 James B. Francis of Lowell, past president of the 

 society, presented one describing some tests, made 

 under his direction, to determine the efficiency of a 

 Humphrey turbine water-wheel of large power (about 

 275-horse power), lately put into one of the mills of the 

 Tremont and Suffolk manufacturing company at Low- 

 ell. The test showed an efficiency of about eighty- 

 two per cent, which was considered satisfactory. Mr. 

 Francis also presented a paper giving the results 

 of a large number of experiments, which he had 

 made in connection with this turbine test, to deter- 

 mine the coefficients of the formula for the flow of 

 water over a submerged weir, or one in which the 

 level of the water on the down-stream side is above 

 the crest of the weir. Experiments on weirs of this 

 kind have not been very numerous, especially with 

 large quantities of water. The maximum quantity 

 in Mr. Francis's experiments had been somewhat over 

 two hundred cubic feet per second, and his paper 

 gave the proper constants to be used in the ordinary 

 formula for cases of this kind. His results must be 

 considered as of great value, and as forming a wor- 

 thy supplement to his former extended experiments 

 on ordinary weirs. 



Mr. A. M. Wellington read a paper on a line of 

 railroad which he had located from Vera Cruz to the 

 City of Mexico, comparing it with an existing line 

 built some time ago. Although the elevation sur- 

 mounted was the same in both cases (about 8,050 

 feet), the old line had a grade of 216 feet per mile 

 for most of the distance, and had cost over three 

 times the estimated cost of the new line, which had 

 a continuous grade of 106 feet to the mile for a dis- 

 tance of about eighty miles, broken in but one place 

 by a level stretch of half a mile, at an important 

 station. This is probably the longest unbroken grade 

 in the world. The maximum curvature was about 

 the same in both lines, though rather sharper in the 

 case of the new line,, where the smallest radius was 

 about 300 feet. 



Mr. P. C. Asserson of Norfolk gave the results of 

 his experiments in endeavoring to protect wood from 

 the ravages of the Teredo navalis. He had tried 

 some twenty different preservatives, both paints and 

 substances to be injected into the wood, and had 

 found nothing effective except creosote. Leaving 

 the bark on piles, or incasing them in a sheathing of 

 plank, was also stated to be effectual, as the Teredo 

 could not cross a seam, and therefore could not pene- 

 trate the pile under these circumstances. In the dis- 

 cussion on this paper it was stated that covering piles 

 with yellow metal had proved effectual, as the ani- 

 mal would not pursue its ravages within the distance 



so covered, even^though it might be able to gain ac- 

 cess to the wood on either side of the metal. It was 

 therefore only necessary to cover piles with the metal 

 down to the mud bottom, or a little farther. Driving 

 small-headed nails thickly all over the surface of the 

 pile was also said to have preserved piles for over 

 seventy years, by preventing the entrance and growth 

 of the animal. 



Mr. Robert Moore of St. Louis described the land- 

 ing arrangements for a car-ferry across the Mississippi 

 River at St. Louis. The ordinary range of the water 

 being about thirty-one feet, and the current very 

 swift, the problem had presented some difficulty; 

 and it had been necessary to protect the bank of the 

 river, for some distance above and below, by willow 

 mattresses sunk with stone in the ordinary way. 

 The details of the arrangement adopted were shown 

 by drawings. 



Mr. D. Fitzgerald of Boston read a paper on the 

 rainfall at Lake Cochituate, discussing the results of 

 observations extending from 1852 to the present time. 

 His results differ somewhat from those obtained by 

 Mr. Schott, in his work on rainfall, published among 

 the Smithsonian contributions, on account of the 

 longer period at the command of Mr. Fitzgerald. 



The application of the water-power of Niagara to 

 the generation of electricity was the subject of an in- 

 teresting paper by Mr. Benjamin Rhodes of Niagara 

 Falls. He estimated the average power as seven 

 million horse-power, on the total fall, including the 

 rapids above, of two hundred and thirty feet; and the 

 cost of the plant necessary to utilize this power, 

 transform it into electricity, and transmit it any- 

 where within a radius of five hundred miles, was 

 placed at five thousand million dollars. About six 

 thousand horse-power is now in use at the falls, the 

 greater part on the hydraulic canal, which takes 

 the water from the extreme head of the rapids, and 

 discharges it below the falls, using it on the wheels 

 under heads of from fifty to a hundred feet. Water- 

 power has been used to run a Brush dynamo since 

 1879, for lighting the grounds of Prospect Park. 

 The speaker calculated that there would be a saving 

 per light, at the city of Buffalo, by using the Niagara 

 water-power instead of steam-power, of forty dollars 

 per annum. The well-known advantages of the 

 water-power at Niagara, as regards steadiness, etc., 

 were dwelt upon. 



Capt. O. E. Micharles, U.S. A., discussed the heavy- 

 gun question, taking the ground that it would be 

 better for the government to make large contracts 

 with private establishments for the manufacture of 

 heavy cannon, than to establish a government foun- 

 dry for their manufacture, and advocating the em- 

 ployment of a Rodman gun, cast from open-hearth 

 steel, annealed from the interior. 



The most important business action taken by the 

 society was a vote to memorialize the president of the 

 United States, asking that the president of the society 

 be appointed a member of the international confer- 

 ence to meet at Washington in October next, to fix 

 and determine a prime meridian from which time 

 should be reckoned. The committee on standard 



