iv PREFACE 



formulas are shown in many cases by practical 

 examples and solutions, together with expla- 

 nations. 



The material is conveniently arranged for 

 ready reference. Particular attention has been 

 given to the weights of various materials. Most 

 tables on weights are incomplete and it is often 

 necessary to search some time before the weight 

 of any particular material can be ascertained. 

 It is hoped that this volume will obviate tedious 

 work of this kind. 



The section on tests of cement will be found to 

 contain useful information that is usually found 

 only in special treatises on the subject. 



INTERNATIONAL CORRESPONDENCE SCHOOLS, 



July, 1911. Scranton, Pa. 



