Intelligence and MiscellanecfUs Articles. 4-83 



has also shown, by the analytic method, that these two substances 

 may be considered as amides of malic acid, corresponding to oxa- 

 mide and oxamic acid. If this be the case, synthesis should repro- 

 duce asparagin and aspartic acid. The action of ammonia on malic 

 sether, when this sether shall be prepared, ought to give rise to as- 

 paragin. The author states, however, that he has not been more 

 fortunate than his predecessors in his attempts to obtain malic sether ; 

 but he has succeeded in preparing aspartic acid with bimalate of am- 

 monia. 



When this salt is heated from 160° to 200° (Centig.) in an oil-bath, 

 it fuses and swells, and disengages some very slightly ammoniacal 

 water. The residue is a reddish, transparent, resinous-looking 

 mass, which is very slightly soluble even in boiling water. By 

 repeated washings with hot water, a pulverulent, amorphous mat- 

 ter is obtained, which is of a pale-brick colour and an earthy 

 taste. It is a new nitrogenized acid, which differs in all its re- 

 actions from aspartic acid. This substance is very stable. It dis- 

 solves in hot concentrated acids, from which water precipitates it 

 unchanged, even after boiling for a short time. But if it be heated 

 for five or six hours with nitric acid or with hydrochloric acid, it 

 undergoes a remarkable transformation. The reaction is over when 

 water, added to the acid solution, ceases to precipitate anything. 

 The solution, evaporated in a water-bath to dryness, left a brown 

 residue, crystalline and very acid, which is a compound of hydro- 

 chloric acid and organic matter. This compound is easily purified 

 by charcoal, and fine colourless crystals are obtained. It was dis- 

 solved in a large quantity of hot water, and the solution was divided 

 into two equal portions, one of which was accurately saturated with 

 ammonia, and then added to the other portion. On cooling, a great 

 quantity of small brilliant prisms were formed, which were aspartic 

 acid; it did not possess the same form as the acid obtained from 

 asparagin, but the salts which it forms with lime, soda, and with the 

 oxides of copper and silver, crystallize in the same form as the cor- 

 responding aspartates ; and the author ascertained by analysis that 

 they contained the same quantity of base ; the acid submitted to 

 analysis gave the same results as those obtained from the compound 

 of aspartic acid. — Comptes Rendits, Mars 18, 1850. 



DESCRIPTION OF AN APPARATUS FOE REGULATING THE HEAT 

 PRODUCED BY A GAS-BURNER. BY ALEXANDER KEMP. 



Any one who has had occasion to maintain an object at a regu- 

 lated temperature for a length of time by means of a gas-burner, 

 must have experienced the difficulty of keeping the heat at the re- 

 quired point from two causes. First, the quantity of gas passing 

 tlirough the burner in any given time varies directly as the pressui'e 

 on the service-pipes ; a greater quantity is therefore consumed when 

 the pressure increases, and the amount of heat applied to the object 

 is increased in the same degree. 



Secondly, as the temperature of the atmosphere is liable to change 

 during the continuance of the experiments, its cooling influence will 

 be greater at one time than another. Both these causes conduce to 



