30 OPERATIONS OF FUEL-TESTING PLANT IN 1905. 
atmosphere with a very low dew-point and not subject to large percentage variations, and 
the results obtained are considerably more concordant. Another advantage of this method 
is that it greatly shortens the time of air drying, so that the samples can be prepared in 
much less time than formerly. A detailed description of the apparatus will be presented 
in the complete report. 
As it has been clearly demonstrated in the earlier work of the laboratory that there was 
a marked loss in moisture in many samples during the reduction of the air-dried sample and 
the weighing out for analysis, the system of sampling in this respect has been radically 
changed. The sample is ground in tight jars with quartz pebbles, in a ball mill. The 
ground sample is placed in wide-mouthed bottles and the sample for analysis mixed and 
weighed direct therefrom without pouring out and mixing, as was done in the earlier work. 
Direct comparison between samples reduced in this way and those ground on a bucking 
board or in an open mortar shows a distinct difference in the percentage of moisture, due 
to changes from the exposure during sampling. 
PERSONNEL. 
The personnel of the laboratory at present is as follows: Prof. E. E. Somermeier, in charge; 
Mr. F. M. Stanton, head chemist; Mr. G. A. Burrell first assistant ; Messrs. Karl M. Way 
and E. C. Waters, assistants. 
WORK DONE IN THE LABORATORY. 
From May up to January 1 the laboratory has received over 1,000 samples, representing 
coal from nineteen States and three Territories. The proximate analyses and sulphur deter- 
minations have been made on practically all of these, and the ultimate analyses, determina- 
tions of the heating value, and other special determinations have been made on such of the 
samples as have required the additional work. 
In addition to the regular routine work on the coal samples, some tests on tars and some 
laboratory work on the washing of coal have been conducted, while a limited number of 
experimental lines of work have been followed up, in so far as the time at the disposal of the 
laboratory force has permitted. 
Analytical results are presented in the detailed report on each sample (pp. 53-233). 
