On Sal Nitrum ana JVitro- Aerial Spirit 21 



the solar rays, is considerably increased in weight, 

 as has been ascertained by experiment. Indeed, we 

 can scarcely imagine any other source for this increase 

 of the antimony than the nitro-aerial and igneous 

 particles fixed in it during calcination. 



I am aware that it is the common opinion that 

 the diaphoretic virtue of antimony is due to the 

 loss of its extraneous and combustible sulphur in its 

 calcination. But I am not sure that this view is 

 quite consistent with truth. For it is well known 

 that if antimony and nitre are mixed and thrown 

 into a heated crucible, a very impetuous flame will 

 arise from them, since the sulphur of the antimony 

 ignites the nitre mixed with it. If, however, the 

 antimony has detonated (as the chemists phrase 

 it) with about a double quantity of nitre, then 

 nitre mixed with it will no longer produce a flame, 

 since the combustible sulphur of the antimony has 

 been entirely removed in the first detonation. And 

 still the antimony has not yet acquired the diapho- 

 retic virtue. Hence, for its further fixation, charcoal 

 or some sulphureous matter should be put from time 

 to time into the crucible in which the antimony, 

 along with the nitre last added to it, has been fused, 

 so that the nitre may ignite and the antimony be 

 fixed by its long-enduring flame. Clearly, then, the 

 fixation of antimony appears to be caused, not so 

 much by the removal of its extraneous sulphur, as 

 by the fixation in it of the nitro-aerial particles in 

 which the flame of nitre abounds. 



The reason why an addition of tartar to nitre 

 contributes greatly to the fixation of antimony is 

 obvious from what has been said. For I think it 

 must be attributed to the tartar being imbued with 

 such sulphur as is suitable for gradually and thoroughly 



