REPORT OF NATIONAL MUSEUM, 1919. 17 



less, being 2.512 cents against 2.795 cents the year before. This 

 was due primarily to the fact that steam was required for heating 

 purposes a greater number of days than usual, although the winter 

 was mild, so that the production of current was to a certain extent 

 a by-product. 



The coal furnished by the Government fuel yards was extremely 

 poor and not suited for the type of stokers in the Museum. After 

 the 1st of April a better grade was furnished. In addition to the 

 increased cost of coal the cost of the removal of ashes was several 

 hundred per cent greater than ever before, due to the large amount 

 of ash in the coal and great increase in cost for cubic yard in re- 

 moval. 



The total amount of coal used was 3,156.50 tons, of which the 

 Bureau of War Risk Insurance paid for 499.88 tons. 



Owing to the closing of the building and its use for office pur- 

 poses a heavier electrical load was carried, which with the change 

 in the operating force and the impossibility of keeping on a suffici- 

 ent number of men caused greater wear and tear on the machinery. 



Among the important changes made in the plant during the year 

 which will materially aid in its operation v/as the purchase of an 

 oiling system for the main bearing of the engines which has never 

 been satisfactory. By the use of this apparatus the oil passing 

 over the main bearing flows by gravity to a large receiving tank in 

 the pump pit from which it is lifted by a double-ended steam pump 

 to a filter placed on the main engine room floor, where all dirt and 

 entrained water is removed. The pump then lifts the oil from the 

 filter to a receiving tank near the ceiling of the engine room in 

 which is a continuous pipe coil for circulating cooling water. From 

 this tank the oil passes by gravity back to the reservoir on each 

 engine, thence to the individual bearings. It is expected that this 

 arrangement will do away with the common danger of burning the 

 main bearings of the engine, and will greatly prolong the life of 

 the bearings. 



The ventilating system for the engine room, which had been 

 exceedingly unsatisfactory', has been changed, greatly improving con- 

 ditions. The 30-inch fan originally installed for forcing hot air 

 from the engine room into the rooms and shops in the east hall base- 

 ment is now utilized for forcing fresh air through a system of ducts 

 running along the ceiling of the engine room. And provision has 

 been made for more efficiently heating the adjacent rooms and shops 

 by the installation of radiators connected with the hot-water system. 



The ice plant was operated 5,215 hours, producing a total of 331.8 

 tons of ice at a cost of $3.70 a ton. Although the cost of ice was less 

 than the preceding year, it was still much higher than it should have 



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