88 Properties of Wood Ashes. 



ness for a considerable time. In this case there could be no donbt 

 of the presence of carbon ; yet after cooling, the mixture weigh- 

 ed just four handred and eighty grains, and consequently had 

 suffered no ponderable loss. 9. I now placed the crucible as it 

 came from the furnace in the eighth experiment in a smith's 

 forge, and heated it to incandescence for several minutes. At 

 this heat the ashes lost nine grains, leaving at least four grains 

 of the adventitious carbon unconsumed. 10. Four hundred and 

 eighty grains of sifted ashes, hot from the stove, were put into 

 the crucible, and exposed to the highest heat of a smith's forge 

 for twenty minutes. On cooling, they weighed only four hun- 

 dred and thirty one grains, having sustained a loss of forty nine 

 grains ! The ashes in the middle of the surface were gray, but 

 all other parts throughout were bluish brown, or blackish and 

 brown. The mass was porous, considerably contracted, and 

 cracked through the centre nearly to the bottom of the crucible ; 

 it crumbled under considerable pressure, but retained its form in 

 water, yielding up its soluble parts without falling to pieces. 

 Throughout the slag were scattered grains of a beautiful cerulean 

 hue, insoluble in nitric or sulphuric acid, and exhibiting under 

 the microscope a botryoidal surface. These grains were evidently 

 the product of the intense heat of the forge ; and if we can sup- 

 pose a sufficient quantity of alumine present in the ashes, what 

 forbids them being Hauyne of domestic manufacture? 



During this last crucibulation, care was taken, as before, to pre- 

 vent the escape of ashes; the crucible was kept erect and well 

 covered with a steel plate, and every precaution used to avoid 

 error. Add to this vigilance, the fact that the ashes did not oc- 

 cupy more than one third the depth of the crucible, and we can 

 hardly conceive that reverberating currents of air from the bel- 

 lows, could dissipate any of the ashes. But to determine whether 

 the loss was attributable to such an accident, or to the loose state 

 of the ashes, I tried experiment 11. Seven hundred and twenty 

 nine grains of hot, sifted ashes, were pressed into the crucible, 

 and carefully heated in the forge for fifteen minutes. The loss 

 was seventy grains, or 9.6+ per cent. The ashes were scorified, 

 and presented the hauynoid grains and every other appearance 

 and property of the slag of the tenth experiment. If no ashes 

 escaped, how shall we account for the loss of weight ? Is there 

 a ponderable element in ashes, which has eluded former analy- 



