BIOCHEMISTRY: ABEL AND PINCOFFS 
513 
tained in this country. We accordingly purchased two hundred 1 cc. ampullae 
of this product, which is described on the labels as a "sterile solution, 1 : 1000, 
of the isolated active substances from the glandula pituitaria." We did not 
inquire if a preservative is used in its preparation, as the presence of a sub- 
stance of this character would hardly interfere with the isolation of a proteose. 
The residue from ten ampulles, as obtained by evaporation at a low water- 
bath temperature under an electric fan and subsequent drying over sulphuric 
acid, amounted to 0.0154 g. The dry residue from the two hundred 1 cc. 
ampulles would therefore have weighed 0.3080 g. One hundred and ninety 
cubic centimeters, that is to say, the total quantity of solution with the excep- 
tion of the 10 cc. used for the estimation of the dry residue, were concentrated 
on the water bath under the fan to a volume of 2.5 cc.^ and saturated with finely 
powdered ammonium sulphate. The characteristic gummy precipitate of 
salted-out albumose immediately collected on the stirring rod and on the sides 
of the tube containing the solution. The precipitate was washed with sat- 
urated ammonium sulphate solution, decomposed with barium hydroxide and 
the freed albumose was precipitated as a "sulphate" with absolute alcohol 
and ether in the manner already described. Dried over sulphuric acid, the 
albumose thus obtained weighed 0.017 g. The reactions were those already 
described — a beautiful pink biuret, a positive Pauly and a negative Knoop 
reaction. Potassium ferrocyanide and acetic acid also failed to give a pre- 
cipitate, showing that coagulable proteids and primary albumoses were not 
present.. 
The ammonium sulphate filtrate from the gummy albumose precipitate still 
gave a fine pink biuret reaction, as was the case also with all the American 
preparations under the same conditions. The addition of a drop or two of a 
very concentrated solution of trichloracetic acid to this filtrate caused an 
immediate precipitation of gummy droplets. These give the biuret reaction 
with great intensity and represent a further yield of albumose with a probable 
admixture of peptone and traces of other substances. It may be stated in this 
connection that the ammonium sulphate filtrates of our American prepara- 
tions also give with trichloracetic acid a precipitate which is indistinguishable 
in its reaction from that obtained with hypophysin. A certain amount of 
albumose or peptone still remains in these ammonium sulphate filtrates even 
after the use of trichloracetic acid. 
The Hoechst preparation is no doubt a clean product and certainly 
contains less dry residue than the products prepared in this country. 
We have seen that the dry residue of ten 1 cc. ampulles of hypophysin 
was 0.0154 g. The dry residue of ten 1 cc. ampulles of Armour's 
Pituitary Liquid was 0.0242 g. and in its relatively smaller content in 
proteoses this prepration more nearly approaches hypophysin than any 
other examined by us. It is to be understood that we are not criticizing 
these products because they happen to contain more or less albumose. 
