370 PAGES. 107 ILLUSTRATIONS. DEMY 8vo. 

 PRICE 155. 



WHAT IS HEAT? 



A PEEP INTO NATURES MOST 

 HIDDEN SECRETS. 



BY FREDERICK HOVENDEN, F.L.S., F.G.S., F.R.M.S. 



PLAINLY WORDED, WITHOUT TECHNICALITIES, EXACTLY 

 DESCRIBED. 



PRESS REVIEWS. 



(1) Chemical News: "This is a very remarkable book, and the outcome 

 of a remarkable work. . . . The first section of the book is a criticism of 

 'mathematical and physical concepts.' The aim of the discussion is to dis- 

 establish the mathematician from what we should have considered his 

 unquestionable position of leadership in the affairs of science. Mr. Hovenden 

 twits him with the unreality of the most ordinary of mathematical operations. 

 . . . Section II. is devoted to destructive criticism of the kinetic theory. We 

 commend this section, as indeed the preceding, for a collection of well-chosen 

 excerpts from the writings of Clerk Maxwell and others who have contributed 

 to the elaboration of this remarkable theory. . . . The succeeding section on 

 ' Gravitation and Weight ' is similarly devoted to correcting ' the confusions 

 with which the specialists have surrounded themselves.' Clerk Maxwell and 

 Lord Rayleigh are especially singled out for treatment on account of their 

 pronouncement that gravitation is not a force. . . . The last sections of the 

 book are the most original by far. They contain a careful description of a 

 number of very interesting experiments and observations, preceded by a 

 'statement of the case,' or a priori formulation of the author's view of the 

 micro-cosmos. This view is nothing less than remarkable. There are very 

 few scientific men who are prepared with anything like a complete credo in 

 regard to the constitution of matter, of the still more 'elusive' quantity 

 known as ' ether.' Mr. Hovenden has given us an object lesson of boldnes's 

 in reducing the results evidently of years of thought to a comprehensive 

 statement in twenty-three ' articles. ' The author's most important conclusions 

 are that ' the ether ' is an ' anti-gravitating fluid ' ; that the atoms and 

 molecules the ultimate forms of matter are of variable form and dimensions ; 

 the difference in dimensions is due to variations ' of the quantity of ether held 

 by them at a given moment, and is what is called the temperature of the atom 

 or molecule ' ; and lastly, that both ether and molecules may be brought to 

 visual demonstration, may be seen under conditions which it has been a main 



