212 EDWARD H. SANBORN 



d3'namos. Four small engines connected to ventilating fans 

 represent about 50 horsepower. For the hydraulic elevator 

 service there are 5 pumps, 1 of about 150 horsepower, 1 of 105 

 horsepower, 1 of 100 horsepower, and 2 of 40 horsepower each. 

 Altogether, the engines and pumps in this one office building 

 represent an aggregate of about 1,000 horsepower. A con- 

 siderable part of this equipment is duplicate machinery, pro- 

 vided for emergencies, but not less than 700 horsepower is 

 used continuously in the building. From this may be judged 

 the importance of this use of power, which has developed 

 almost entirely since 1890. 



The use of steam power, either directly applied or elec- 

 trically transformed and transmitted, is becoming more and 

 more general in mining and quarrying, in public works of 

 every description, in the sinking of foundations, in the erec- 

 tion of buildings, and in nearly every branch of industry, and 

 the amount of power used, apart from manufacturing opera- 

 tions, is increasing steadily. 



The application of power to diversified operations as in- 

 dicated above, has been most noteworthy during the past 

 fifteen years ; and it is easy to see, even without any definite 

 statistical presentation, that while the power used in manu- 

 facturing in 1890 probably embraced by far the largest part 

 of the motive power applied to all purposes, similar figures 

 for 1900 represent a much smaller proportion of all the power 

 used in the United States. 



In view of the generally prevailing belief that mechanical 

 power has been and still is very largely supplanting hand labor 

 in almost every branch of industry, it may appear strange 

 that with an increase of 101.8 per cent in the total number of 

 manufacturing establishments between 1880 and 1900, and 

 with an increase of 142.2 per cent in the total value of prod- 

 ucts during the same interval, the proportion of manufactur- 

 ing establishments reporting the use of power was the same 

 in 1900 as in 1880 — about one third. In 1880 the use of 

 power was reported by 85,923 out of 253,852 estabhshments, 

 or 33.8 per cent. In 1890, 100,735 out of a total of 355,415 

 establishments reported the use of power, or 28.3 per cent of 

 the aggregate. The reduced proportion was doubtless due 



