( 9S7 ) 
Very hard to dilfolve ^ the Particles of Sea-Salt being, as 
it were, imprifoned among the Particles of the Salt' of 
Urine, it comes to pafs, that many of the Aqueous Parti- 
cles, penetrating at firft da(h the Saline Panicles of the 
Urine^ do there immediately lofe much oi tlieir Motion ^ 
and this Motion grows weaker by fa much the more, as 
the Aqueous Particles meet afterwards with Saline Particles 
of another Nature, whofe Refiftance is much more confi- 
derable, than that ot the Salts of Urine.. So in the firft 
Inftance of the Diffolution, the Motion of a great quanti- 
ty of Aqueous Particles bejng very much abated all at once, . 
by the Salts of Urine, and by- the Sea Salt, it excited, in a. 
few moments, a Cold far greater than the Cold of other 
Diflblutions of Salts, which the Water does not penetrate 
fo readily. 
It may be Objefted, that the Sea-Salt being the hardeft 
to Diflblve, its Diffolution would be alfo the Coldeft. To 
which I anfwer, that this might be if the Water coukl pe- 
netrate fuddenly into all its parts: but the flownefs with 
which it penetrates them,becaufe of the ciofe Texture of the 
Molecules of this Salt, does hinder that the Biminution of 
the Motion of the Parts of the Water^ can't be fo ready, 
nor by confequence fo great : Whereas in Sal Armofiiac, 
the Parts of the Sea-Salt being extended by the Sak of 
Urine, the Pores of the Alkalous Salt of Urine are like fo 
many Ways open to the Parts of the Water, for going to 
penetrate the Parts of the Sea-Salt in numberlefs places. ' . , 
I place in the Rank or Cold Dilioiutions, an Experi- $aiim Difohd- 
ment which MonliQur Ho mherg made (ome time ago, be- ^JJ'"^'''-^^*"^'-^ 
fore the Society^ and which I believe will not be amifs if^^" 
I fhould repeat it here 5 becaufe it ferves to prove that 
which I am going to fay about the Cold of Sal Armoniac 5 
the Experiment being otherwife not very common. Tis 
made thus : Take a pound of Corrofive Sublimate, and a 
pound of Sal Armonuic^ powder them, each apart ^ then 
mix. both the Powders very exaftly, put the Mixture into ^ 
a 
