48 OPERATIONS OF FUEL-TESTING PLANT IN 1905. 
briquettes for domestic use are not usually more than 2 pounds nor less than one-fourth 
pound in weight. The smaller briquettes are usually of biscuit or lenticular shape, whereas 
the larger briquettes for railroad use are generally square or prismatic, with slightly rounded 
edges. 
PRELIMINARY TESTS IN BURNING BRIQUETTES ON LOCOMOTIVES. 
Two hundred tons of Arkansas semianthracite slack coal from the mines of the Western 
Coal and Mining Company were made into briquettes for the purpose of preliminary tests 
concerning their suitability for use in locomotives. Twelve tons of this coal were made, 
on a Renfrow machine, into biscuit-shaped briquettes averaging about 10 ounces in weight. 
The remainder was made into briquettes 4| by 6| by 2J inches, averaging in weight about 3^ 
pounds. From 6 to 62 per cent of pitch was used as a binding material in all these bri- 
quettes. 
After a few tests on a switching engine to determine the best method of firing these 
briquettes, two tests were made on the locomotive drawing the regular passenger train of 
the Missouri Pacific Railway from St. Louis to Sedalia, Mo., a distance of 188 miles. On a 
similar run made by this passenger train, with the same engine and fireman, lump coal was 
used from the Consolidated Coal Company's mine No. 17, at Collinsville, 111., this being taken 
as a good average of the coal ordinarily used by the Missouri Pacific Railway. The water 
and coal consumed were in each case carefully weighed, but in these preliminary tests no 
records were made of the steam pressures and temperatures of the feed water. 
The engine steamed freely on each of the three tests. No clinkers were formed on the 
grates or tube sheet with the Illinois bituminous coal. A light clinker was formed over the 
grates with both runs on the Arkansas coal, which, however, did not interfere with the 
engine making the required amount of steam. The tube sheet clinkered on the run using 
Renfrow briquettes, and it was necessary to clean off the clinker at Jefferson City, 125 miles 
from St. Louis. In both tests with briquettes they burned almost without smoke and were 
reported as being a satisfactory fuel for locomotives in the service of this railroad. The 
mechanical engineer of the company, under whose supervision these tests were made, 
expresses the opinion that the advantages gained in burning the briquettes were more than 
sufficient to.cover the cost of their manufacture. 
However, the above tests must be considered as simply preliminary to more careful tests 
to be made later, and these additional tests must be made at an early date. 
PARTIAL BIBLIOGRAPHY OF BRIQUETTING. 
The following list includes a number of articles on the briquetting of fuels, which may be 
found interesting and useful. In a later publication this list will be enlarged by the addi- 
tion of a number of titles and notes on the several papers. Meanwhile this briefer list will, 
it is believed, answer the purpose for which it is intended. 
1594. 
Piatt, Sir Hugh [pamphlet on briquetting; said to be the first known literature on the subject.] 
1776. 
Jars, Herr [pamphlet said to be the oldest German literature on briquetting]. 
1861. 
Gerondeau, H., Notes sur l'agglomeration des charbons menus: Revue universelle des mines. 
1864. 
Oppler, , Die Fabrikation kunstlicher Brennstoffe. 
1868. 
Pole, Dr. W., Notes on the original manufacture of coal: Polytechnisches Central blatt, pp. 343, 654. 
1869. 
Pole, Dr. W., Notes on the original manufacture of coal: rolytechnisches Centralblatt, p. 1374. 
