108 THE MICROSCOPIST. 



Alcohol coagulates albuminous matter. 



Ether dissolves fat. 



Acetic Acid will dissolve phosphate or carbonate of lime, 

 but not the oxalate. 



Nitrate of Barytes in cold saturated solution is a test for 

 sulphuric and phosphoric acids. The precipitated sulphate 

 of baryta is insoluble in acids and alkalies. The phosphate 

 is soluble in acids arid insoluble in ammonia. 



Nitrate of Silver. A solution of 60 grains to the ounce 

 of water is a convenient test for chlorides and phosphates. 

 Chloride of silver is white, soluble in ammonia and insolu- 

 ble in nitric acid. The tribasic phosphate of silver is yel- 

 low, and soluble in excess of ammonia or of nitric acid. 



Oxalate of Ammonia is a test for salts of lime. Dissolve 

 the material in nitric acid, and add excess of ammonia. 

 Dissolve the flocculeut precipitate in excess of acetic acid, 

 and add the oxalate of ammonia. Oxalate of lime is in- 

 soluble in alkalies and acetic acid, but soluble in strong 

 mineral acids. 



Iodine is a test for starch, coloring it blue. Albuminous 

 tissues are colored yellow, and vegetable cellulose a brown- 

 ish-yellow. The addition of sulphuric acid turns cellulose 

 blue. 



DETERMINATION OF SUBSTANCES. 

 ALKALIES. 



Bichloride of platinum precipitates from salts of potash 

 or ammonia a yellow double chloride, which crystallizes 

 in beautiful octahedra. It has no precipitating effect on 

 solutions of soda. Polarized light will distinguish the 

 800,000th of a grain of double chloride of sodium and 

 platinum by its beautiful colors from the chloride of 

 potassium and platinum, or of platinum alone. The 

 double chloride of platinum and potassium may be dis- 

 tinguished from that of ammonia by heating to redness, 

 treating with hot water, and acting on with nitrate of 



