[ 205 ] 



XXIX. Heat produced by Moistening Pulverized Bodies*. 

 By Tito Martini f. 



rpHE phenomena discovered by Pouillet$, regarding the 

 -L production of heat by the moistening of porous bodies, 

 are well known, and since Pouillet man} r experiments have 

 been made by Cantoni§, Melsens||, Chappuislf, E. Wiede- 

 mann**", and Meissnerft- 



Notwithstanding the investigations of these philosophers, 

 however, I believe that it may be of some interest to publish 

 the results of my own researches in this direction, which are 

 more extended than those of the savants referred to. 



Among the numerous results contained in my paper 

 I will select the most complete, that is to say, those concern- 

 ing chemically pure animal charcoal, believing that such 

 important manifestations are due to a different method of 

 experimenting adopted by me ; consisting of an arrange- 

 ment whereby the liquid ascended to the powder, which was 

 placed in a glass tube separated from it by a piece of light 

 linen cloth. 



Table (8th of the original paper) . 



Name of the liquid, 



Temp, of 

 the air. 



Temp, of 



the liquid. 



Temp, of 

 the charcoal. 



Mas. temp. 



Increase of 

 the temp. 



Distilled water 



18-10 

 18-09 

 17-10 

 1830 

 18-30 

 17-10 



1751 



17-82 

 16-82 

 18-22 

 18-52 

 1712 



o 



17 92 



18-28 

 17-20 

 18-48 

 18-70 

 17-50 



3350 

 35-75 

 34-70 

 37-42 

 36-30 

 38-10 



15-58 

 1747 

 17-50 

 18-94 

 17 60 

 2060 



Absolute alcohol 



Acetic ether 



Benzine 



Bisulphide of carbon... 



Owing to this mode of conducting the experiment, I was 

 enabled to observe that when the rise of temperature was not 



* "Intorno al calore che si sviluppa nella umettazione delle polveri, - ' 

 Atti del H. Istituto Veneto, t. viii. serie 7, Mag-gio 1897. 

 t Communicated by the Author. 



X Annates de Chirnie et de Physique, 2 me serie, t. xx. p. 411. 

 § Atti del R. Istituto Lombardo, Maggio 1866. 

 i| Memoir es de V Academie royale de Belgique, t. xxiii. (1883), 

 U Wiedemann's Annalen, t. xix. p. 21 (1883). 

 ** Ibid. t. xxv. p. 145 (1885). ft Ibid, t xxix. p. 114 (1886). 



