165 



li inches in diameter, from the want of proper arrangement on the 

 part of the riggers for securing the regular and equal lowering at all 

 points of suspension, an excess of weight was thrown upon the hooks 

 on one side, by which one of them was broken, and almost at the 

 same instant all the hooks gave way, either breaking or bending 

 open, and the machine was allowed to fall about fifteen feet. The 

 weight of the falling mass was about 90,000 lbs., but part of this, 

 about 28,000 lbs., was counterbalanced by twelve weights attached 

 to it by chains passing over pulleys. The gravitating force being 

 about 62,000 lbs. acting upon a mass of 118,000 lbs. The damage 

 to the machine was inconsiderable, and no person received any in- 

 jury, although nearly a hundred men were at work around and within 

 it. The gasholder, of which this is part, is believed to be the largest 

 in the world ; its diameter is 1 40 feet, height 70 feet, and capacity 

 over a million cubic feet. 



The weight of iron used in its construction is 330,000 lbs., chiefiy 

 sheet and bar. The guide frame contains over a million pounds of 

 cast iron; it is composed of 144 columns arranged in twelve stands 

 or groups placed all around the tank ; each group consists of four tiers 

 of columns and entablatures, the lower tier fashioned after the Tus- 

 can order, the second Doric, the third Ionic, and the upper Corinthian. 

 The cost of the entire structure, including the excavation and walling 

 of the tank, is about $85,000, which is about i40,000 less than the 

 cost of an equal quantity of gas store room in gasholders of the usual 

 capacity, say 200,000 cubic feet. 



The pending nominations were read. 



Stated Meeting, November 1. 



Present, thirteen members. 



Dr. Franklin Bache, Vice-President, in the Chair. 



Letters were read : — 



From the Royal Society of Edinburgh, dated Edinburgh, 

 20th December, 1848, acknowledging the receipt of Vol. IX. 

 Part 3, of the Transactions, and No. 34, of the Proceedings of 

 this Society, and announcing a donation to the Society: — 



From the same, dated Edinburgh Royal Society's Apart- 

 VOL. V. — z 



