INTRODUCTION. 11 
(2) The separation of the tar and other by-products from the gases made in the pro- 
ducer and the commercial recovery of these by-products, or the fixing of the tar and other 
hydrocarbons as available gases for power purposes. 
(3) The use of slack coals in the gas producer and the value of the sizing of lump coals 
for producer purposes. 
(4) Utilization of blast-furnace gases and gases from coke ovens for power purposes. 
DETAILED REPORTS OF TESTS. 
Reports in detail of the results of the various tests described are printed on pages 53-233. 
It will be noted that the form and order in which the various test tables are arranged dif- 
fer from those used in the reports on the fuel tests made during 1904. « In the present 
report the test records are grouped together under the respective coal samples and the 
samples are presented by States in alphabetical order. That this method of publication 
is an improvement will be apparent. 
ANALYSES OF ALASKA COAL. 
By way of cooperation with the Alaska division of the United States Geological Survey 
the laboratory of the fuel-testing plant at St. Louis analyzed 34 coals, samples of which 
were collected in the Bering and Matanuska River coal fields by Mr. G. C. Martin, one of 
the assistant geologists of the Survey. These analyses are to be found on pages 230-231 
of this report. 
INVESTIGATION OF PEAT. 
Arrangements are being made for an examination of the nature and fuel value of peat 
from a number of localises in the different States. Prior to the writing of this report peat 
from but one locality (Massachusetts) has been tested through the producer and gas engine. 
The results of this test are given on page 134. The peat was collected, cut into small frag- 
ments, pressed into crude bricks approximately 3 by 6 by \\ inches in size, and the mois- 
ture reduced, by air drying, from 85 to 45 or 50 per cent. In this form the peat was fed 
into the producer at the rate of 600 to 750 pounds per hour. The results of the test were 
eminently satisfactory. The peat burned freely, evenly, and completely. The gas had a 
fuel efficiency of 166 British thermal units per cubic foot of gas, as compared with 142 to 
159 British thermal units per cubic foot of gas made from bituminous coal. The engine 
was run continuously during this test under full load. This same peat, cut into small 
fragments, but in a loose and wet condition (containing 80 to 85 per cent of moisture), 
did not burn satisfactorily in the producer, and attempts to dry this loose peat in the Bart- 
lett direct-heat rotating dryer were unsatisfactory, owing in part, probably, to lack of 
time for readjusting the equipment to suit the unusual conditions imposed on it in hand- 
ling the peat. 
Shipments of peat from a number of other localities will be tested during 1906 and efforts 
will be made to develop better facilities for handling the unbriquetted material. 
LITERATURE RELATING TO PEAT AND ITS UTILIZATION. 
The following list will be found to include a number of articles of interest on the charac- 
ter and extent of peat deposits and the methods through which they are utilized in different 
countries. In a subsequent and more elaborate report on this subject the list of articles 
will doubtless be enlarged and descriptive notes will be added. 
1810. 
Cook, G. H., Geology of New Jersey, p. 481. 
1835. 
Hitchcock, C. H., Reports on geology of Massachusetts. 
a Bull. U. S. Geol. Survey No. 261, 1905; Prof. Paper U. S. Geol. Survey No. 48, 1906. 
