22 



4 hours of peptic digestion, did not yield products giving a 

 heat-precipitation test. 



g. From the above it is obvious that, with the exception 

 of the product obtained at the end of 1/2 hour of peptic diges- 

 tion of osseoalbumoid, none of the products gave a heat pre- 

 cipitation test, thereby differing from elastoses which have 

 properties not unlike the Bence Jones protein in some respects. 

 However, these products as obtained above, after passage 

 through the body, might be so changed that, when excreted in the 

 urine, they would give reactions like those of the Bence Jones 

 protein. On this basis the following experiments were tried. 



B. SUBCUTANEOUS INJECTION OF PRODUCTS OF THE PEPTIC 

 DIGESTION OF OSSEOALBUMOID. First Experiment. The dog 

 in this experiment was under observation in the laboratory 

 for two days previous to the injection and during that time 

 his urine gave no precipitate on heating, but saturation with 

 (NH 4 ) 2 SO 4 produced a small amount of yellowish precipitate 

 soluble in H 2 O. On heating this solution, no precipitate was 

 formed, nor did it give a reaction with picric acid or trichlora- 

 cetic acid. The solution gave the spectroscopic picture of 

 urobilin. The urine, however, gave a marked precipitate 

 with potassio- mercuric iodid. This precipitate dissolved on 

 further heating and reappeared on cooling. The urine did 

 not give a precipitate with picric acid or trichloracetic acid. 1 



1 It was thought that the reaction with potassio-mercuric iodid might 

 be due to the fact that the dog had a considerable amount of muco-puru- 

 lent material in the inner canthus of both eyes and that this material 

 had gotten into the urine. Some of this material from the eyes was 

 obtained, made into a solution with 0.85 per cent. NaCl, filtered, and 

 on adding potassio-mercuric iodide gave a faint precipitate, which did 

 not disappear on further heating, however. As the solution was com- 

 paratively concentrated, it was diluted until its content of material was 

 equal to about the maximum proportion that could be present in the 

 urine. At this dilution a marked clouding, but no precipitate, appeared 

 in the test with potassio-mercuric iodide. 



The infection of the dog's eyes was removed by irrigations with boric 

 acid, and the cage in which the dog was kept, was thoroughly cleansed. 

 The urine continued to give the reaction with potassio-mercuric iodid, 

 however, after the muco-pus as a factor in its production was ruled out. 

 (See the foot-note on the opposite page.) 



