Abstract This paper deals with one of several types of fuel used in heating houses. It sets forth the burning characteristics of coke when used for this purpose as shown by work done by the U. S. Bureau of Mines and others. Of the solid fuels, anthracite and coke are truly smokeless and are held in high regard for this quality. Ways are being found for making commercial coke from a wider range of coals than heretofore, and the use of coke for domestic heating is increasing.