PREFACE 



The main object of this book is to bring to the attention of 

 engineers an accurate and rational method of estimating the loss 

 of heat from steam pipes and boilers covered with any of the well 

 known non-conducting materials now on the market. This 

 method worked out long ago by P6clet seems to have been 

 generally overooked in this country, perhaps because no trans- 

 lation of Peclet's work existed. 



The principles involved are so general in their application 

 that it is believed that the fuller explanation of them, to be found 

 in the appended translation, together with the experiments on 

 which they are based, will be of some general interest. This 

 matter will be of use to heating engineers in cases which are not 

 taken care of by their usual rules, and of great value as an aid 

 to the cultivation of that broad view of a problem so necessary 

 to practical success. To the refrigerating engineer and designer 

 of cold storage warehouses these principles are indispensable. 



