119 Eitaminailon of ihi Furlt;/ of MfdUintii t^tt 



Muriatic Acid*. 



COMMONLY called fpirit of fait, always contains iron, and frequently fulphuric acid 

 and copper. 



The fulphuric acid is deteded either by the addition of barytcs, or acetite of lead, and 

 the refults are the fame as in the foregoing experimeats. 



Copper is inveftigated by fuperfaturating this acid with pure ammoniac, which in this 

 cafe will immediately be tinged of a perceptible blue. 



Iron is manifclled by previoufly uniting this acid with carbonate of potafh and treating 

 it then with tinfture of gall-nuts, or pruffiate of potafli. The firft will produce a black, 

 and the latter a blue precipitate. 



The fpecinc gravity of muriatic acid {hould be, 1,70 to 1,000. 



Pure muriati c acid is totally deftitute of colour. 



Acetous Add. 



THE concentrated acetous acid commonly met with contains fulphuric acid, witk' 

 which it is either fraudulently adulterated, or with which it is impregnated by a carelefs 

 and flovenly management during the procefs for obtaining it. 



We often find this acid contaminated by tartareous acid, and not unfrequently by cop- 

 per or lead. The prefence of fulphuric acid is here alfo difcovered by the addition of 

 barytes, or acetite of lead, in the manner already mentioned. 



Tartareous acid is detected by faturating the acetous acid with vegetable alkali, in con- 

 fcquence of which a tartarite of potafh becomes feparated in the form of a white powder. 



Copper is difcovered by faturating the acid with carbonate of ammoniac, and lead be- 

 comes manifefted by mixing it with water impregnated with fulphurated hydrogenous 

 gas. In the firft cafe a blue, and in the fecond a black precipitate will be formed. 



The fpecific gravity of the moft concentrated acetous acid fhould be to that of water 

 as 1,050 to 1,000. It is colourlefs, and of a penetrating fmell. 



Dljlllled Vinegar. 



VINEGAR, if not diftilled In glafs veffels, but in a ftlll with a pewter head, always con- 

 tains lead in folution. 



To difcovcr this, equal quantities of vinegar, and water impregnated with fulphurated 

 hydrogenous gas, are mixed together, which mixture, if the vinegar is free from lead, will 

 remain unaltered ; whereas, on the contrary, the fmalleft quantity of this metal will pro- 

 duce a black precipitate. 



We frequently meet with diftilled vinegar adulterated with fulphureous acid, the pre- 

 fence of which is detedted by means of nitrate of barytes, or acetite of lead, as mentioned 

 before. 



• The proportion of fulphuric acid prefcribed by our royal college of phyficians for obtaining this acid is much 

 too great, as 18 or to ounces are quite fufficient for a total decompofition of the quantity of muriate of pouih 

 ordered. 



The 



