76 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



the purpose of avoiding or diminishing smoke, it will be suf- 

 ficient to cause an intimate admixture of the gases the mo- 

 ment they quit the lire, even without introducing a fresh 

 volume of air. This principle has been applied in several 

 forms. In one, two fireplace's are built side by side, running 

 parallel, and separated by a wall. The fires in these two 

 fireplaces are fed alternately, and, the currents of gas being 

 directed one against the other at the back of the furnaces, 

 the strata are thus broken up and mixed, so as greatly to di- 

 minish the amount of smoke. Another application for the 

 same purpose consists in introducing a little air, in a finely 

 divided state, behind the bridge of the furnace. This air 

 supplies the requisite oxygen at the moment when the com- 

 bustible gases are still sufficiently heated for them to become 

 ignited ; and the admixture is readily effected, but with some 

 loss of combustible matter. Still a third process, that "of 

 Thierry, consists .in introducing a jet of steam over the sur- 

 face of the fire. The steam does not exert any chemical ac- 

 tion, but operates mechanically by mixing gases, and thus 

 diminishing the amount of smoke. By means of these, and 

 other applications that will readily suggest themselves, much 

 may be done not only in preventing the escape of smoke from 

 furnaces, locomotives, and hearths, but also in economizing 

 the fuel by securing an appreciably greater intensity and 

 amount of heat. 14 A, 1870, July 9, 22. 



HYGRAITIXITY. 



In a paper on the " Estimation of Antimony," published in 

 the Chemical JYeios, Hugo Tamm calls the attention of chem- 

 ists to a new phenomenon, which the author describes under 

 the name of u hygraffinity." This phenomenon was discov- 

 ered in a peculiar compound of antimony bigallate of anti- 

 mony which is totally insoluble in water, and yet possess- 

 es a powerful affinity for moisture, which it absorbs rapidly 

 from the air, after being dried at the temperature of 212 F. 

 jNIost powders and precipitates, dried at that temperature, as 

 is well known, absorb moisture on exposure to the atmos- 

 phere, but this is a purely physical phenomenon, due to po- 

 rosity. On the contrary, in the case ofgallate of antimony, 

 chemical affinity is at work, and this precipitate, after expo- 

 sure to the air for two or three hours, actually absorbs two 



