24 MISCELLANEOUS PAPERS. 



Braddock's campaign against the French and Indians in 1755 many 

 horses a were lost from eating mountain laurel. The plant was intro- 

 duced into France by Michaux. 6 In 1802 George G. Thomas c per- 

 formed some experiments with Kalmia latifolia and K. angustifolia 

 on himself, on a friend, and on some dogs. These experiments he 

 embodied in an inaugural dissertation which was presented to the Uni- 

 versity of Pennsylvania. Six to 15 grains (0.4 to 1.0 gram) of the 

 dried leaves produced distinctly unpleasant symptoms — rapid pulse, a 

 feeling of fullness with pain in the head, throbbing of the temples, 

 with nausea, vomiting, and dilatation of the pupils. In dogs the 

 administration of a decoction of 30 grains (2 grams) was followed 

 by marked salivation, with stupor, rapid respiration and purgation, 

 paralysis, and finally convulsions. Thomas made the interesting ob- 

 servation that if the laurel was mixed with lard the toxic symptoms 

 were much lessened. He examined the distillate from the leaves for 

 an essential oil. but failed to find any. 



After Thomas, several experimenters reported on the action of 

 mountain laurel upon themselves. Bigelow,^ who saw the dried 

 leaves taken in doses up to 20 grains without producing symptoms, 

 questioned if the leaves had a specific action, and traced any injurious 

 effect they might exert to their indigestibility. Others, as Osgood, e 

 Stabler/ and an anonymous author in the Boston Medical and 

 Surgical Journal, volume 10, page 213, reported severe symptoms on 

 themselves. 



This action was compared with that of Veratrum.^ From this 

 time on few reports of experiments were published, yet the number 

 of cases of poisoning in stock reported to the Department of Agri- 

 culture induced the Commissioner to call attention to this subject, in 

 his report of 1863. h Sheep are the animals usually reported as 

 affected by the plant. Under ordinary conditions, however, eastern- 

 bred sheep will not eat the plant unless they are starved or their 

 supply of green or attractive food has been cut off. 



As is well known, most of the cases of poisoning occur in winter,' 

 when the laurel is the only green plant around, although western-bred 



a Barton, B. S., 1. c, p. 60. 



6 Browne, D. J. Trees of America, p. 364. 



e Thomas, G. G. Inaugural Dissertation on the Kalmia Latifolia and Angus- 

 tifolia, Philadelphia, 1S02. 



d Bigelow, J. Amer. Med. Bot, vol. 1. p. 140, 1S17. 



e Bigelow, J., 1. c, vol. 3, p. 185, 1820. 



f Stabler, R. H. On Kalmia Latifolia. Amer. Jour. Pharin., n. s., vol. 10, p. 

 241, 1845. 



9 Medical Properties of the Kalmia Latifolia. Boston Med. and Surg. Jour., 

 vol. 10, p. 213, 1S34. 



h Report of the Commissioner of Agriculture for 1S63, p. 242. 

 ' Remarkable Instance of the Absence of Animal Instinct. Penny Magazine, 

 vol. 7, p. 2S3, 1838. 

 121—11 





