C 503 ] 
order that I could oblerve, but fo as on the whole 
to make a very beautiful appearance; in this cry- 
ffallifation the fait feemed to form in clumps, two 
of which are to be feen at b> b , &c. and a profile 
view of a fmall piece at c , c> and a figure of fome 
of the plates laid on their flat fides at d, d. 
Did the difference of the age of the verjuice em- 
ployed in thefe two experiments, or the difference 
of the proceffes they underwent, make the difference 
in the appearance of the falts obtained in the diffe- 
rent cryffallifations ? The fait of the old verjuice 
approached to that of vinegar ; of the new to that 
of apples. 
Experiment V. 
With the acid of perry. 
At the time I gave in this paper, in the beginning 
of November, I had made feveral attempts to ob- 
tain a neutral fait from perry (or the fermented 
juice of pears) but without fuccefs, owing to the 
large quantity of faccharine juice with which this 
liquor abounds. But having accidentally left fome 
of the concentrated liquor in a fmall china bafon, 
on examining it fome days after the prefen t hard 
frofl: had begun, * I found that a cry flail ifation had 
taken place. 
The cryftais were flat, long, narrow, very thin 
tranfparent plates, fuch as reprefented in fig. 17; 
they were from a quarter of an inch to near an 
* The account of this experiment was given to the Royal 
Society about the middle of January 1768. 
inch. 
