From Introduction: "A summary of the tests made at St. Louis and a resume of the conclusions to be drawn from the tests and from the opinions of gas-producer manufacturers on the status of the gas producer and gas engine was published in a Survey bulletin in 1907. As it is desirable to repeat much of the material that appeared in the former bulletin (now out of print), this presentation may be regarded as a revision of the previous one, although considerable information not previously available for publication has been added."

From Introduction: "The present bulletin, published by the Bureau of Mines because of the analyzing and testing of fuels have been transferred from the Geographical Survey to the Bureau of Mines, briefly reviews the status of the coke industry, some features of practice in the use of coke in the foundry, the probable happenings of a cupola heat, and the reasons for modifying charging practice so that a particular coke can be used to best advantage."