﻿34 Canculian Record of Science. 



It is very evident, then, tliat the fibrous matter of this 

 charcoal is simply absorbed slag. Two questions of inter- 

 est then arise. What were the conditions in the furnace 

 that caused charcoal in large quantities to absorb and 

 retain the licjuid slag ? How did it happen that only on 

 two occasions had the joroduction of this slag-saturated 

 coal been observed ? 



The following particulars regarding the furnace are 

 data that must be taken into consideration in any theory 

 put forth to explain the peculiar behaviour of the char- 

 coal under consideration : — 



Four 'oh inch tuyeres are used. 



The average pressure of blast is about 5 j lbs. 



Tlie average temperature of blast, 900 degrees Fahr. 



The quantity of air, as a rule, is 2,638 cubic feet, but 

 at times it has run to as high as 2,827 cubic feet to the 

 minute. 



Cubical contents of furnace, from stock-line down 

 1,264 cubic feet. 



IS 



Charcoal Impregnated with Slag. 



By D. p. Penhallow, M.A.Sc. 



On the 8th of October last I received from Prof. J. T. 

 Donald a sample of charcoal, together with some peculiarly 

 fibrous silicious matter, accompanied by the statement 

 that the coal was received from " clients who use charcoal 

 in the production of charcoal iron," and that " when 

 the coal is burned it leaves an ash consisting of long 

 fibres. This material was thrown out at the cinder notch 

 in large quantities unconsumed. The coal was made from 

 oak and apparently bass-wood and elm." 



Upon submitting the coal to examination, it became 

 evident that it was derived from the wood of an elm — 

 probably the common white or American elm {Ulmus 



