[ -83 ] 



6'^' Examine the liquor out of which the falts have been 

 taken; if it do.s not efFervefce with the marine acid, evaporate it 

 to drynefs and weigh the refidiuum ; — if it does efFervefce with 

 acids, faturate it with the vitriolic or marine and evaporate it 

 to i of the whole; when cool take out the faline refiduum, 

 evaporate the remainder to drynefs and weigh it, this gives the 

 coaly matter, which may be tried by projeding it on melted nitre, 

 with which it will deflagrate ; the ^ of this coaly matter call the 

 coaly fuppUment of i lb. I fliall fuppofe it to amount to 1 2 grs. and, 

 denote it by C. 



7*'* The filtred- water. No. IV. is next to be gently evaporated 

 to nearly one pint, and then fufFered to reft for three days in a 

 cool place that it may depofite its faline contents, if it contains 

 any, and thefe being taken out the remainder muft be evaporated 

 nearly to drynefs, and its faline and other contents examined. 

 How this ftiould be done I fhall not mention, the methods being 

 too various, tedious and of too little confequence ; few falts occur 

 except gypfum, which is eafily diftinguifhed ; the water may be 

 examined as to its faline contents when it is evaporated to a 

 pint ; if any faits be found, call them the faline fupplement, and 

 denote them hy S' ; I fhall fuppofe them here=4 grains. 



8*" We now return to the boiled earthy refiduum. No. IV. 

 which we fhall fuppofe fully freed from its faline matter, as, if 

 it be not, it may eafily be rendered fo by adding more hot 

 water; let it then be dried as in No. III. is mentioned. Of this 

 earthy matter thus dried weigh off one ounce, deducing one- 

 twelfth 



