EDITORIAL. 503 



temperature rises high the poisonous principle is developed. This 

 is due to a conversion of part of the orthophosphoric acid into the 

 pyro form, a reaction familiar to chemists. 



This explains in an interesting way the differences which have 

 been observed in the meal from different mills. Several experiment 

 station workers have expressed the belief that the process of manu- 

 facture often has an important relation to the poisonous properties 

 of the seed. At one station pigs were fed continuously and heavily 

 on cotton-seed meal from a nearby mill without the slightest injury 

 being apparent, but when a change was made to a lot of meal shipped 

 in from an adjoining State cases of poisoning soon followed. Less 

 easily explained is the observation of Dr. Crawford that Sea Island 

 seed grown in Florida proved poisonous even without heating, ap- 

 proaching in this respect certain varieties of the Upland cotton. 

 This remains for further invastigation. 



In the study of the extract containing the digestive products, it 

 was found that lead and copper acetates preci[)itated a toxic agent 

 which gave the usual symptoms of cotton-seed meal poisoning when 

 fed to rabbits, while the lihnite from this precipitate remained in- 

 active. On decomposing the lead precipitate with sulphuretted 

 hj^drogen and concentrating in vacuo, a red gunnny material was 

 obtained which fed to rabbits produced an intense gastro-enteritis 

 and induced death in about an hour. From this material crystalline 

 needles were obtained after standing about eight Aveeks, but these 

 crystals proved physiologically inactive, while the gummy matrix 

 continued to produce the poisonous effects, suggesting that the active 

 principle was an amorphous body. One after another suspected 

 compounds were eliminated from consideration and the active prin- 

 ciple was shown not to be a toxalbumin, a glucosid, and probably 

 not an alkaloid. But it yielded precipitates with ammonium molyb- 

 date, magnesia mixtures, and the acetates of such metals as lead, 

 mercury, and cadmium, indicating the presence of some form of phos- 

 phoric acid, which ultimately j^roved to be the case. The substance 

 responded to reactions for pyrophosphoric acid, which is known to 

 have poisonous properties, and is a soft glassy mass crystallizing only 

 at low temperature and after months of standing. 



It is interesting to note that as far back as 1892, Prof. M. B. 

 Hardin, of the South Carolina Experiment Station, reported the 

 finding of both meta and pyrophosphoric acid in all of a series of 

 samples of cotton-seed meal which were examined in his laboratory. 

 He says of their j)resence : " The salts of the last two acids are said 

 to be more or less poisonous, and though their precise physiological 

 action has not I believe been determined, it is quite possible that some 

 of the peculiar and in certain cases injurious and even fatal effects 

 produced by the use of cotton seed and cotton-seed meal as feeding 



