STEAM TESTS. 
By L. P. Breckenridge. 
INTRODUCTION. 
The following is a preliminary report of the steam tests of the coals 
burned under the boilers of the United States Geological Survey 
coal-testing plant at the Louisiana Purchase Exposition, at St. Louis. 
This report consists of (a) a short description of the methods used 
in testing and a table giving the important dimensions of the boilers 
used; (b) a list of the various coals tested, and (c) some of the impor- 
tant results of the tests. 
METHODS OF CONDUCTING TESTS. 
The method of testing fuels under boilers has been a subject of dis- 
cussion for many years by the members of the American Society of! 
Mechanical Engineers, and as the result of this discussion a standard 
method of conducting tests and of reporting the results has received 
the approval of this society. The steam tests of coal at the Geological 
Survey testing plant have been conducted and the results reported in 
accordance with these methods and forms. 
The number of tests made was 78. The duration of each was planned 
for ten hours, and was as near this time as the conditions at the close 
of a test would permit. An experienced and careful fireman hand-fire 
all of the coals tested. 
DESCRIPTION OF THE BOILERS. 
There were two 210-horsepower Heine safety boilers provided for 
these tests. They were exactly similar in construction and setting. 
Each was provided with its own stack, 115 feet high and 37 inches in 
diameter. Each boiler was fed by its own independent injector, and! 
no other means of supplying water to the boilers was provided. The 
ends of the blow-off pipes were visible during all tests. 
In the next table the leading proportions of one of the boilers arc 
given. 
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