Proceedings of the Convention of Agricultural Chemists Held at Atlanta, Ga., May 15th, 16th, 1884 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1884 Excerpt: ...portion of it to be dissolved by the citrate of ammonia. The solvent action of this reagent on bone phosphate, must not be forgotten in the final determination of the meihod of estimating phosphoric acid. One of my students, Mr. H. A. Huston, made some experiments with a fine raw bone to determine the influence of time and temperature on the amount of bone dissolved. Following are his results: INFLUENCE OF TIME ON AMOUNT OF BONE DISSOLVED. Time, 30 min. Per cent. total. 20.28 Temperature 60. Per cent. Insoluble. 13-94 14.61 14.65 Mean 14.40 Per cent. 6.34 5.67 5.63 5-88 Soluble in citrate. Next a series of determinations was made to find the influence of time on the amount of bone dissolved. The results appear in the following table: These results are of great interest wherever much bone is found in fertilizer. The action of citrate on rock phosphate is much less and perhaps can be disregarded for commercial purposes. VHITE PYROPHOSPHATE. In all the directions which are given for the determination of phosphoric action as a pyro-magnesian salt, we are told to ignite the precipitate until it is white. I have had great difficulty in securing this' theoretically white precipitate, especially in the determinations of soluble and reverted acid derived from fertilizers containing organic matter. I should like to know what the experience of others has been in this direction. I sometimes brighten the precipitate somewhat by moistening it with fuming nitric acid, drying and reigniting. By a repetition of this method, I am able to get a grayish white residue. I have been struck, however, with the fact that this precipitate differed so little in weight from its original dark colored self, as to be of very little consequence in the final computations. As a result of thi...