412 MR HENRY HOW ON MECONIC ACID, 
I have nothing to add descriptive of the acid to what little has been men- 
tioned. It is a white powder as precipitated by acids from the yellow compound, 
crystallising from concentrated solution in hot water in a crystalline crust. 
The yellow salt has a peculiar appearance. It does not present the least crys- 
talline structure even under the microscope, but consists of round translucent 
granules ; when deposited slowly from dilute fluids these have the appearance of 
small yellow vesicles or air-bubbles. It is readily soluble in hot water with a 
decided smell of ammonia; it is very sparingly soluble in hot, insoluble in cold, 
alcohol. It gradually loses ammonia when heated in the dry state at 212° Fahr. ; 
at a higher temperature it blackens and fuses. 
I have adopted the name of Meconamidic Acid for the acid of this salt, as 
simply expressive of its constituents, without any reference to the molecular 
arrangement of its elements. 
Coupled Acid Ether of Meconic Acid. 
The substance I have described as occurring in the process of making the ethers 
of meconic acid, when rectified spirit is employed. is deposited generally after the 
first product of ethylomeconic acid is filtered off. I have sometimes observed it 
also falling from the mother liquor, from which the first deposit had been crys- 
tallised, and also in the course of purification of the residue left on evaporation of 
the original acid mother liquor. Its constant occurrence induced me to examine 
if it were a substance of determinate composition ; I accordingly redissolved some 
of it in hot water, it which it is extremely soluble, twice or thrice, and obtained, 
on cooling of the liquid, a white amorphous powder. I select the analyses of two 
specimens, treated in this manner :— 
7-655 ... carbonic acid, and 
4660 grains, dried at 212°, gave 
I 
1-311... water. 


5-335 grains, dried at 212°, gave 
II. < 8-712 ... carbonic acid, and 
LeOhD so. ge Water. 
Calculation. 
I. Il. —————— 
Carbon, . 5 44:80 44:53 44°85 Ca Lez | 
Hydrogen, ; 3°12 2-73 2°80 Hy, 12 
Oxygen, : mec aoe 52°35 O,, 224 
100-00 428 
I am inclined to think the approximation of the above numbers to the per-cent- 
ages corresponding to the formula given, in a substance purified from different 
preparations, is too close to be accidental, and that the body in question is a de- 
terminate compound. The formula given contains the elements of one atom of 
meconic and one of ethylomeconic acid, 
Cy, Hy, 0.,=8 HO, C,, HO,, +2 HO, C,H,0 C,, HO,,. 

