f 9 ] 
To find the proportion of water that fhould be added to each 
portion of acid, in order that it fhould contain the given pro- 
portion of flandard, I ufed the following analogy: let the quan- 
tity of water to be added to 400 parts of the acid that the 
mixture may contain 48 per cent. ftandard be «. 
Then 400+. 354 :: 100. 48, then 19200+ 48 x= 35400. 
16200 
And 48 x= 35400—19200=16200. And carro Perk ke 
In this manner I found the quantities of water to be added 
to each of the other portions. The mixtures being made, they 
were fet by for four days, ftirring them with a glafs rod (that 
remained in them) each day, and the sth day they were tried; 
after which the half of each was taken out and as much water 
added to them, and then fet by for three days, by which means 
the fpecific gravities correfponding to 24. 23. 22. 21. 20. and 19. 
per cent. ftlandard were found, after which 6 more portions of 
400 grs. each of the concentrated acid, whofe fpecific gravity 
was 1,8393, were taken the proper proportion of water added 
to each, and after three days reft and repeated agitation, their 
denfities in temperature 60° were examined as above, by which 
means the fpecific gravities correfponding to 36. 34. 32. 30. 28. 
and 26. per cent. ftandard were obtained, and half thefe portions 
mixed with half water exhibited, after three days reft and 
agitation, the denfities correfponding to 18.17. 16. 15. 14. and 
13. per cent. ftandard in the above temperature. The balance 
I ufed turned with ;; of a grain when charged with two ounces, 
Vo. IV. Cc and 
