ter of an hour it began manifeftly to freeze the vapours and drops of water 
on theoutfideofthe Glafs. And when the frigorifick power was arriv’d at 
the height ,1 feveral times found,that water, thinly plac'd on the outfide 3 whilft 
the mixture within was nimbly ftirr’d up and down, would freeze in a quar- 
ter of a minute (by a Minute-watch*) At about \ of an hour after the infri- 
gidating Body was put ity the Thermofcope,that had been taken out a while 
before,and yet was rifen but to the loweft freezing mark , being again put in 
the liquor, fell an inch beneath the mark. At about houres from the firfl: 
Solution of the Sait 1 found the tinned liquor to be in the midft between the 
freezing marks, whereof the one was at 5$ inches ( at which height when the 
Tinfture refted, it would ufually be, fome, thongh but a fmalI,Froft abroad 
and the other at 4^ inches •, which was the height, to which ftrong and dura- 
ble Frofls had reduced the liquor in the Winter. At 3 . hours after the begin- 
ning of the Operation, I found not the Crimfon-liquor higher than the upper 
Freezing mark newly mention’d ^ after which ,it continued to rife very flowly 
for about an hour longer- beyond which time i had not occafion toobferve it* 
Thus far the Note-hoc^ wherein there is mention made of a Circumflance 
of fome former Experiments of the like kind , which I remember was very 
confpicuous in this newly recited. .For, the frigorifick mixture having been 
made in a Glafs -body ( as they call it ) with a large and flattifh bottom , a 
quantity of water, which I (purpofely) fpilt upon the Table, was by the ope- 
ration of the mixture within the Glafs, made to freeze , and that ftrongly 
enough, the bottom of the Cucurbite to the Table • that ftagnant liquor being 
turn’d into folid Ice, that continued a confiderable while unthaw’d away, 
and was in fome places about the thicknefs of a half Crown piece. 
Another Obfervadon, made the fame Spring, but lefs folemn , as meant 
chiefly to fhew the Duration of Cold in a high degree, is recorded in thefe 
terms : The firfl: time, the Seal'd Weather-glafs was put in, before it touch’d 
the common water,it flood at 8^, having been left there a confiderable while, 
and once or twice agitated the water, the rinded liquor funk but to , or at 
furtheft^fithen the frigorifick liquor being put into the water with circum- 
ftances difadvantagious enough,in(about)halfa quarter of an hour the rinded 
liquor fell beneath • and the Thermofcope, being taken out , and then put 
in again,an hour after the water had been firfl infrigidatedjfubfided beneath 5 
inches, and confequentlv within \ of an inch of the mark of the flrongly freez- 
ing weather* 
7. Whereas the grand thing, that is like to keep this Experiment from be- 
ing as generally Vfefptl , as perhaps it will prove Luciferom , is theDearnefs 
of Sal Armoniack -, two things may be offered to leffen this Inconvenience* 
For fir ft, Sal Armoniack might be made much cheaper, if infteadof fetching 
it beyond- fea,our Country-men made it here at home • (which it may eafily 
be, and l am ready to give you the Receipt , which is no great Secret.) But 
next,! eonfideredjhat probably the infrigidating vertue of our mixture might 
depend upon the peculiar Texture of the Sal Armoniack. whereby, whileft the 
Water is diffolving it, either fome Frigorifick particles are extricated and 
excited.or (rather) fome particles .which did before more agitate the minute 
parts of the water , areexpell’d (or invited out by the ambient Bodies) or 
