Properties of Wood Ashes. 89 



ses ? Or did the intense heat of the forge decompose some of the 

 constituents of ashes, drive off the gaseous elements, evaporate 

 water of composition, and volatihze any of the soh'ds ? Regard- 

 ing the known constituents of ashes, I ascertained that in one 

 specimen of the scorified ashes there was a trace of caustic Hme ; 

 I detected it in no other portion of the slag. Water in which the 

 scorified ashes had digested several days, produced a very faint 

 white cloud, on the addition of oxalate of ammonia. Another por- 

 tion of the water boiled down, exhibited a lively effervescence on 

 the addition of an acid. The slag from the crucible, though ex- 

 posed to a damp atmosphere for several days, showed no disposition 

 to deliquesce. The long digested and thoroughly washed scori- 

 fied ashes, produced abundant effervescence with nitric acid; the 

 resulting nitrate had the peculiar bitterness of that salt of lime, 

 and produced a very copious white precipitate with oxalate of 

 ammonia. I judge, therefore, that but a very small quantity of 

 carbonic acid was driven off from the carbonates of lime and of 

 potash ; not more perhaps than would be counterbalanced by the 

 oxidation of the iron contained in ashes. The presence of sili- 

 ca, iron, and a sulphate, were satisfactorily shown ; an accident 

 prevented me from testing the presence of a phosphate or a chlo- 

 ride. It therefore remains with me a moot question, what occa- 

 sioned the loss in the tenth and eleventh experiments? 



Since the publication of my former communication on this 

 subject, I have received information of other accidents similar to 

 those reported to this Journal, where large quantities of stored 

 ashes had become extensively heated, and sometimes the wooden 

 repository inflamed. In several instances it was known that hot 

 ashes had been thrown upon the heap, under the impression that 

 there was as much safety in doing so, as in depositing them upon 

 the ground remote from combustible matter. What part the 

 small portion of pulverulent coal may perform in the propagation 

 of the fire, I am not prepared to say. That coal in some degree 

 of comminution is necessary to the passage of caloric from one 

 part of the mass to another I am convinced ; and that charcoal 

 in some state of division exists in most wood ashes, is easily 

 proved by the use of a coarse sieve, to say nothing of the large 

 coals generally apparent, and especially as they float upon the 

 water of the leach-tub. It may here be asked, if this combusti- 

 ble material is thus distributed through the ashes, why does not 



Vol. xmi, No. 1.— April-June, 1842. 12 



