274 Profotion of Aid in Sahs,^c, 



But with regard to the marine acid itsfp. grav. is to be inveftigated according to the or- 

 dinary mathematical rules. 



Prob. 3. To find bow tfiuch water muft be added to 100 parts of an acid liquor of a 

 given fp. grav. to bring it down to another lower given fp. grav. 



ifl. Find by the table the quantities of acid anJ water in 100 parts of each of the acid 

 liquors refpedtively, each being fuppofed to be in the table, let the quantity of water in the 

 denfer be W, and the quantity of acid = A, let the quantity of water in the lefs denfe = w, 

 and the quantity of acid = a, and the quantity of water -to be added to 100 parts of the 

 denfer =m: then W + « muft be to A as w to a. And W a + « ot = A w. And 



a m =■ hw- — W a. And m = . 



a 



Prob. 4. Given weights of two or more add liquors of different fp. gravities being mixed, 

 to find the quantity of real acid in 100 parts of the mixt liquor and its fp. grav. 



Find the fum of the quantities of real acid in 100 parts of the mixture, then find the re- 

 fulting fp. grav. by the 2d problem ; if the given fp. gravities be extratabular, the operation 

 muft be more tedious, as the acid contents of each muft be found. 



Prob. 5. The quantity of an acid liquor requifite to faturate 100 parts of any hafts being 

 found, to find the fp. grav. of that acid liquor. 



I ft. Find by the 4th table the quantity of real acid requifite to faturate 100 parts of the 

 given bafis, it is then plain that the given quantity of acid liquor contains the requifite quan- 

 tity of real acid, fince it is fuppofed to faturate 100 parts of the bafis, and hence we may fee 

 how much loo parts of fucb acid liquor contains of real acid, and if this laft found quantity 

 be in the table, its fp. grav. will be feen, but if extratabular, its fp. grav, muft be fought by 

 the 2d problem. 



Prob. 6. The quantity of real acid requifite to faturate 100 parts of any bafis being known, 

 to find how much of one acid liquor of any given fp. grav. is requifite to faturate that, and 

 confequently any other given quantity of fuch bafis. 



If the given fp. grav. of the acid liquor be tabular the quantity of real acid in 100 parts 

 of it is apparent, and confequently the quantity of fuch acid liquor containing the required 

 quantity of real acid is eafily found by the rule of proportion. But if the given fp. grav. 

 is extratabular, the quantity of real acid in 100 parts of the acid liquor muft be fought by the 

 firft problem. 



Prob. 7. The quantity of real acid in a given quantity of an acid liquor being known, 

 and alfo the quantity requifite to faturate 100 parts of any given bafis. To difcover the 

 quantity of fuch a bafis contained in any folution, or in any powder, by which the given 

 quantity of acid liquor is faturated. 



If the bafis be fingle (that is unmixed with any other bafis to which the acid may unite) 

 or combined only with fixed air, the folution is cafy, but if the given bafes be mixed with 

 other bafes combinable with the fame acid, the folution is more complex and varies accord- 

 ing to the variety of cafes. 



. Prob. 



