VOL. XLI.] PHILOSOPHICAL TRANSACTIONS. 207 



and adapted to it a cover of blue slate, which he had likewise ground with 

 much care. Into this gally-pot he put equal quantities of nitre and flowers of 

 sulphur, about 1 dr. of each. He then fixed on the cover, putting it into a 

 new digester, for 3 or 4 seconds. On opening it the next day, he perceived 

 something had transpired between the top of the gally-pot and the cover ; the 

 top edges of the gally-pot, where the glazing was ground off, being discoloured, 

 though the nitre and sulphur were very little diminished as to their weight ; 

 only they were melted into one lump, which he took out of the gally-pot. 



Having set the empty gally-pot on a shelf, on looking at it the next day, he 

 found long hoary hairs, very bright and brittle, all around the ground edges of 

 the pot ; which he gathered, and, tasting them, found them to be pure nitre. 

 He then set the pot on the shelf again, and in 3 or 4 days, still finding there 

 were fresh shoots made, as large as at the first, he gathered them a second and 

 third time ; so that he supposed the pot Would have continued to have shot 

 fresh nitre much longer, if he had not had urgent use for it, to make other 

 experiments in. However, it is to be observed, that he had already gathered 

 more nitre than he put into the pot at first ; though he had taken all, or nearly 

 all the nitre that he first put in together with the sulphur, out of the pot in a 

 lump. Hence he infers we may have some conception of the nature of mineral 

 earths, and how they increase, when once impregnated with the seeds of a 

 mineral. This is also a proof of the quantity of nitrous particles with which 

 the air abounds, since the large quantity of nitre which he collected out of the 

 pot, when left empty on the shelf, could be supplied by the air only. 



Concermng the Poison of Laurel-Water. By John Rutty, M.D. N''452, p. 63. 



Dr. R. expresses a wish that Dr. Mortimer's experiments with the milk, had 

 more fully determined and ascertained it to be an antidote, than they have yet 

 done. He was informed that some apothecaries in England, being used to 

 sophisticate black-cherry-water with laurel leaves, will not be persuaded, that 

 this is a poison on human bodies, notwithstanding our few instances ; but Dr. 

 R. confirms that it really is so by the following case : 



At Lisminy in Westmeath, a girl of 18 years old, very well and healthv, took 

 a quantity, less than 2 spoonfuls, of the first runnings of the simple water of 

 laurel-leaves ; within half a minute she fell down, was convulsed, foamed at 

 the mouth, and died in a short time, nor was there any swelling on her body. 



VOL. VIII, Q Q 



