136 REPORT OF THE ARCHITECTS. 



cast-iron piping which forms the conductors of rain-water, and the ver- 

 tical soil-pipes. All these heavy pipes have air and water tight joints 

 formed of gasket and lead, and are firmly supported by brick piers at 

 their juncture with the sewer-pipes under ground. 



During the progress of the brick-work temporary supplies have been 

 taken by tapping the pipes supplying the hose-cocks in the Smithsonian 

 grounds, but in the fall a 12-inch main pipe was tapped outside of the 

 building and near its southeastern corner. Three parallel lines of 3-inch 

 water-pipe running due north through the building were put in with 

 supply for 16 fire-plugs, numerous street- washers, outlets for closets, 

 basins, and bath-tubs, stop-cocks, &c. 



Simultaneously with the water supply the supply-pipes for gas were 

 attended to. The gas main was tapped on B street, outside of the 

 southwest corner of the building, and two 4-inch supply -pipes were put 

 in, one running due north and the other due east through the building, 

 at an equal distance of about 20 feet from the outside walls of the build- 

 ing. Both pipes are continued, of reduced sizes, in a similar way until 

 they meet at the northeast corner of the building. They have a regular 

 fall back to the main, the permanence of which is secured by two sup- 

 porting brick piers under each length of pipe, so that no flickering of 

 gas can ever occur in consequence of the formation of traps by irregu 

 lar settlements of the pipes. Outlets have been provided for lighting 

 all the rooms and passages, and also for the light required to supervise 

 all the parts of the building at night. Unusually large gas-pipes were 

 found necessary on account of the great lengths on which they are 

 run, and this feature will afford facilities hereafter, in case it should be de- 

 cided to fit up any of the halls with brilliant light for public use at night. 



14. Underground piping for heating apparatus. — To avoid the unsightly 

 appearance of exposed large-sized steam and water return-pipes required 

 for the successful heating of the vast building, it was decided to build 

 the necessary ducts and introduce the pipes under ground before the 

 floors were laid, though this part of the work was not included in the 

 estimates on which the appropriation for the building proper was based. 



The heating apparatus intended under the estimates, now before the 

 Appropriation Committee of the House, provides for four steam-boilers 

 of 256 nominal horse-power in the aggregate. The generated steam is 

 to be conducted by two separate main pipes of eight inches diameter 

 to about 200 steam -heaters, containing in the aggregate 13,G80 square 

 feet of radiating surface. The hot water condensed in these heaters is 

 to be returned and reused in the boiler. 



FINANCIAL STATEMENT. 



Expenditures up to date.. 

 Earth-work : 



Excavation $724 43 



Grading 129 25 



$853 68 



