400 MEMOIR OF DANIEL TREADWELL. 



without, and from ashes sifting through the cracks and joints, settling everywhere. 

 If admitted through Lirge openings in the floor, these become a source of danger. The 

 heated column in a room like the library hall would rise directly to the ceiling, where 

 it is least wanted, and escape through the porous plaster and the windows, with little 

 benefit to persons on the floor. Hot air affords no radiant heat, and is costly as a 

 vehicle of heat. Hot water, except in the regularity of its working temperature, has 

 few advantages over steam ; the apparatus requires more skill in construction, and is 

 more costly, than for steam. Steam-heating, nowhere common at that time, was gen- 

 erally used in the large rooms of factories. Steam was adopted for the heating of 

 Gore Hall, and from the Lowell Mills were obtained the principal data for this 

 purpose. 



An iron boiler thirty inches in diameter and eighteen feet long was placed in the 

 cellar on tlie east side of the building, connected with a large chimney built for the 

 purpose in the outer wall. Steam was led from this boiler, in an iron pipe six inches 

 in diameter, along the arches of the vaults to four points, two on each side of the 

 hall. From each of these a smaller pipe reached a collection of fifty pipes in the 

 hall above, arranged in a stack ten feet long and eight feet high, with a radiating 

 surface of 286 square feet. Each pipe had within it an air-pipe one quarter of an 

 inch in diameter, which joined others below the floor and ended in the chimney. 

 This method of drawing off the air from steam-pipes was probably first used here. 

 The total radiating surface, 9-44 square feet, was in excess of the steam-making 

 power of the boiler, and of the space to be heated, 171,400 cubic feet. The appara- 

 tus Avas worked at atmospheric pressure only. Steam passed from the boiler 

 through the six-inch pipe to the radiators, and the water of condensation returned 

 through the same pipe to the boiler. The expansion of the air pipe moved a dam- 

 per in the chimney, and controlled the fire. The temperature of the hall was in 

 the coldest weather about 60°, and evenly distributed.* 



A stone building with an iron and slate roof, in an isolated position, and never 

 artificially lighted, gives reasonable assurance of safety from without. With an 

 interior of lath and plaster. Gore Hall would be classed as " slow burning," but by 



* January 2, 1849, the external temperature at evening was —2°, the next morning —4° ; at 10 A. M. +10°. 

 On that day the thermometer, five feet above the floor of Gore Hall, about 1 P. M., was .56° ; at the ceiling directly 

 above, 62" ; at west transept at ceilins, 61° ; five feet above north gallery floor, 64°. With an external tempera- 

 ture of 41°, that of the cellar was 76°, which probably raised somewhat the temperature of the floor above. The 

 boat radiated from the large masses of steam-pipes was found to give a degree of comfort to persons in their vicinity 

 not obtained from warm air alone. The coal consumed was about fifty tons of anthracite annually. In simplicity of 

 construction, safety, and economy, it has not been excelled. Steam-heating has proved satisfactory to the present 

 time in the Library of 1837, nearly half a century, and was adopted in the addition of 1878. 



