5 1 6 Mr. Connell on the Nature of Lampic Acid. 



tained from the liquid by the proper steps. The salt of mag- 

 nesia is highly characteristic, and any one who will prepare 

 it from lampic acid in the manner formerly pointed out, and 

 compare it with crystallized formate of magnesia, will at once 

 see the identity. The properties of the salt of lead are also de- 

 cisive. When the acid liquid was treated in the cold with car- 

 bonate of lead and left some days, the sparingly soluble salt 

 of lead gradually precipitated from the liquid. This salt was 

 then dissolved in water by boiling, and the solution filtered 

 while hot. On cooling characteristic shining spicular crystals 

 of formate of lead precipitated. The whole salt produced 

 by saturating the acid with lead was then treated with alco- 

 hol at the temperature of 100° Fahr. to take up any acetate 

 of lead present ; and a portion of the residual salt was heated 

 with concentrated sulphuric acid. Carbonic acid was evolved 

 in abundance, and was recognised by its usual properties of 

 burning with a pale blue flame and being absorbed by heated 

 potassium. 



Of the presence of formic acid in the lampic liquid not a 

 doubt could therefore exist. To show that it also contained 

 acetic acid, the alcohol with which the lampic salt had been 

 treated was examined, after a little saline matter which made 

 it slightly muddy had subsided and been separated by filtra- 

 tion, when the alcohol was found to contain dissolved a small 

 quantity of a salt of lead ; and as the presence of resinous 

 matter rendered it difficult to examine its properties, a newly 

 prepared portion of it was treated with diluted sulphuric 

 acid and distilled. The acid obtained was neutralized with 

 carbonate of soda, and the solution after being heated to boil- 

 ing mixed with a hot solution of protonitrate of mercury, when 

 a copious deposit of shining scales of acetate of mercury took 

 place, either immediately or on cooling, according to the state 

 of concentration of the liquid*. 



Although the existence of acetic acid in lampic acid was 

 thus established, yet its quantity was small compared to that 

 of the formic acid. It was found that the proportion of ace- 

 tate of lead taken up by the alcohol to that of the undissolved 

 formate was about 1 to 5; and as the latter salt was much 

 more free from resinous matter than the former the real pro- 

 portion of acetic acid was apparently still less than this. 



II. We are now in a condition to judge of the accuracy of 

 the conclusion that in reducing the salts of silver and mer- 



• If a hot solution of formate cf soda is mixed in this way with a hot 

 solution of protonitrate of mercury, an immediate precipitation of metallic 

 mercury ensues with effervescence j and no white salt is deposited either 

 immediately or on cooling. 



