CONTENTS. 
Page. 
Introduction 1 
Accuracy of method of taking car samples 2 
Moisture loss in coarse samples from standing in covered metal pails 2 
Investigation of moisture losses during sampling 3 
Determination of errors due to abrasion of pebbles used in ball mill 4 
Comparison of results of air drying in the special oven and by exposure 4 
Comparison of results for moisture obtained from samples pulverized by various 
methods 6 
Changes in moisture content of fine samples of coal under modified conditions. .' 9 
Comparison of effects of different drying reagents used in the desiccators em- 
ployed in moisture determinations 13 
Effects of varying amounts of sample and of differences in duration of heating 
on results obtained for moisture 14 
Alteration of weight of samples of coal when kept in a finely powdered state 15 
Determinations of specific gravities of the coals 19 
Laboratory methods of determining adaptability of coals to improvement by 
washing 24 
Volatile matter in coals and lignites 32 
Index 41 
3 
