20 EEPORT OF NATIONAL MUSEUM, 1925 



The generating plant has given no special trouble, though it was 

 necessary to install a new set of crosshead shoes on one of the larger 

 engines and to have two of the main bearing boxes rebabbitted. 



Three pieces of new 9-inch pipe for the main that runs along the 

 center of the engine room were also installed. This completed the re- 

 placement of all of the old screw pipe in this line which, during the 

 past three years, had given trouble from leakage. 



An automatic air compressor, driven by a T^-horsepower motor, 

 to furnish 35 cubic feet of free air a minute, has also been purchased 

 to work in conjunction with the Clayton air compressor which has 

 been in continuous service since 1913. This compressor was primarily 

 bought for use in connection with the opening and closing of doors 

 on the elevators, but is intended for additional use in operating 

 machinery in the various laboratories and shops. 



Thirty-two hundred and ninety-two tons of bituminous coal were 

 used in the power plant, and 15.5 tons of anthracite were burned dur- 

 ing the summer in the Natural History Building for domestic pur- 

 poses. 



The total current generated during the year was 476,709 kilowatt 

 hours at a total cost of 2.362 cents a kilowatt hour, a figure that in- 

 cludes labor, material, interest and depreciation on the plant. Cost 

 of current a kilowatt hour omitting interest and depreciation was 

 1.986 cents. 



The testing of the fire-fighting apparatus was continued and 

 equipment inspected in the usual manner. Fire extinguishers were 

 all charged, cleaned, and recharged. Fire plugs for hose connections 

 were flushed in order that they may not become clogged with rust 

 or scale or any foreign substance. There are now ready for use 

 174 carbon dioxide Underwriters' fire extinguishers and four carbon 

 tetrachloride fire extinguishers. The electric fire alarm system was 

 tested at intervals by ringing in each station exactly as would be 

 the case if it were for fire. The alarm system in the buildings has 

 worked better than during the previous year, but it is hoped that at 

 some future date it will be possible to install a closed circuit sys- 

 tem in all the buildings similar to that now in use in the Freer Gal- 

 lery of Art. 



A new compressor for the ice plant has been purchased and will 

 be installed, as the old one was worn out and too small. A number of 

 other changes and repairs have been made in the plant during the year, 

 the condenser having been increased in size by one-third, and a new can 

 filler and 20 cans purchased to replace, others that were unfit for use. 

 With the installation of the new compressor it will be possible to 

 produce 21^ tons of ice a day, whereas the old one had a capacity of 

 only 2 tons. The plant has been in operation 3,645 hours, produc- 



