AMERICAN INSTITUTE. 37l 



It IS alinost as liandy as a lady's perambulator iu the streets and crooked 

 lanes of our town. To-day it climbed Folkstonc Hill, on the old Dover 

 I'oad, I3 miles winding road, having a total ascent of 300 feet, and in some 

 pai-ts a gradient of 1 in 8. This it did to the satisfaction of all present, 

 "with two four-wheeled farm wagons loaded with stone, weighing in all about 

 ten tons. The steam pressure used was from 40 lbs. to 60. lbs, per inch. 

 It took the load up without any apparent difficulty in thirty-five minutes. 

 The engine was then disconnected from the load, the pinion shifted into the 

 first motion, and it run ofi" about two miles at th-e rate of six miles per 

 hour and back. The pinion was again .shifted on to the slow motion, all 

 the wagon wheels were shiddid, and but little steam used in descending. 

 The parts of this machine are few and simple. 



The question for consideration for this evening, viz: *' The setting of 

 steam boilers,^' was then called up. 



Mr. Stetson, one of the committee to examine the Amory furnace, stated 

 that the committee were not ready to report this evening — that Mr. Amory 

 was present and could explain the nature of the improvement. I should 

 like Mr. Amory to illustrate the plan upon the black board. 



Mr. Amory then illustrated upon th<i black board the plan of setting 

 their boilers. The principle Ls as follows : Under the boilers are erected 

 several curved bridges, forming t-hambers, which give the flame and heat 

 a reverbatory motion. The a.sh receiver in these boilers is closed, and hot 

 air is supplied by a pipe under the heat reservoir ; by this method a great 

 saving of fuel is effected, for after all, the question resolves itself into the 

 fact of the amount of evaporation produced by one pound of coal. A ther- 

 mometer had been placed iu the chimney at the end of the boiler, and it 

 was found that it ranged from 300 to 40(j degrees — showing that a large 

 portion of the heat had been expended under the boiler. 



The boilers at the Bible House, in this city, are set on this plan, where 

 they can be viewed. A window has been inserted in the masonry so that 

 the eifect of the mixture of the oxygen of the atmosphere with the various 

 gases generated in the combustion of the fuel can be inspected. 



The Chairman. — At what distance is the bottom of the receiver from 

 the boilers ? and what portion of the circle of the boiler is exposed to the 

 flame ? 



Mr. Amory. — The bottom of the receiver is about three feet from the 

 water, and about one-third of the circle of the boiler is exposed to the heat. 

 By experiments made by Mr. Haswell, for the government, the space was 

 not over eighteen inches. A saving of 15 per cent was reported by him. 

 After deepening the reservoir to about three feet, a saving of 33^ was ob-' 

 tained. 



Mr. Seeley thought the thermometer was not an accurate test at such a 

 high heat. He suggested alloys of diff'erent metals, as a safer guide — 

 these alloys might be made of substances that would melt at known heats. 



Mr, Stetson alluded to his examination of the mode of setting the boilers 

 used at the tunnel at Bergen Hill ; a hot blast was there used. In test- 



