wall at the floor, and to prevent direct drafts on the radiators, those openings were surrounded inside by a wooden screen, 2 feet 8 inches high. The front partition was also opened 18 inches at the ceiling. The piping, as shown in Figure 25, was arranged so that the steam was supplied to the radiators on what is known as the one-pipe overhead system. Steam was supplied to the separator at a pressure of 2 or 3 pounds above atmosphere through a 2-inch pipe from a small heating boiler. The pressure carried at the boiler was slightly in excess of that on the separator, it being throttled at the latter. By this means and by leaving the drip on the separator slightly opened, the steam was supplied free from all entrained moisture. The piping, separator, etc., were all carefully covered. The heat given off was measured by drawing off the condensed steam from the drip pots into cold water and accurately weighing it.
Fig. 22 Prof. Carpenter's Arrangement of Each Radiator and Compartment Removed.
In practically all of the tests made in this plant, one radiator was used as a standard and all the others tested and compared with it. In each test the radiators were connected and a preliminary run made with open air-valves until the conditions became constant and uniform, and a test run made for two to three hours. The radiators were then interchanged and the test repeated. Even with these precautions it was only by exercising the greatest care that it was possible to obtain results which checked closely. It is very remarkable what a decided effect can be created by a very
