the Philadelphia Centennial Exhibition. 
(57 
inclined position, is placed at the greatest possible distance from the fire-box, 
consequently, the engineer has quite a journey to perform between the two. 
I see no reason why the engine should not be vertical and attached to the 
boiler. The pump was particularly defective, and this, and the ignorance of 
those in charge, caused serious delay as well as risk of accidents. The boiler, 
which is large, contains fifty-two pipes which hang down from the dome, and 
ai\' so arranged that a large heating surface is secured. On trial, steam was 
raised in at least one-third less time than in any other engine, and the 
results were good ; this engine taking second place for efficiency. 
Wind-Engines are much more extensively used in the States 
than here, and particularly are they valuable for pumping pur- 
poses, many of the railway companies making use of this power 
to supply their reservoirs. In certain situations, such as the 
open prairie for instance, where more or less wind is a constant 
element, Wind-Engines may be used for other work besides 
pumping, such as grinding, chaff-cutting, &c As storms are 
often severe, it is necessary that the engines should be strongly 
constructed and so designed as to relieve themselves from the 
force of the blast as rapidly as possible. Hence there is much 
ingenuity of design and excellence of workmanship. Some of 
these machines were shown as models in the hall, but three 
i of the more important were erected in the grounds, and to these 
I shall chiefly direct attention. 
I Halladay's Patent Wind-Mills, manufactured by the United States Wind- 
Engine and Pump Company, Batavia, Illinois, are made of various sizes, from 
one-man to 45-horse power. The Kosette principle is adopted, but instead of 
being solid, there are a number of sections on transverse axes. These are 
held straight to the wind during work by means of a balance lever weight 
behind the mill. When the wind increases, the centrifugal force overcomes 
the weight. The sections fly open and present their edges to the wind, and 
Fig. 55.—Ualladay's Patent Wind-Mill in Work, 
