Power and Cambier, Sayre, and Kennedy had previously called attention to the abundance of calcium in the plant, and the writer's investigations confirm this. Pharmacologists are averse to believing calcium given per os poisonous. The writer has, however, fed 5 grams of the acetate of calcium in solution to a rabbit weighing 652 grams. This animal died in two hours, with marked irritation of the stomach, the result being due to the so-called "salt action." Much larger amounts were fed in divided doses, but without injury. Calcium phosphate and calcium sulphate in 2-gram doses proved harmless to a rabbit weighing about 1,400 grams. Three grams of magnesium acetate[172] were fed in solution for five successive days to a rabbit weighing 1,417 grams, but without apparent effect. Strontium acetate c. p., in 2-gram doses, likewise caused no disturbance.[173] No strontium in any amount recognizable by chemical tests was proved in the plant. So that by a process of exclusion the writer was forced to think of barium as the main cause of the trouble. The writer noted that if the ashed plant was extracted with H_{2}SO_{4} water and this extract freed from sulphuric acid with PbCO_{3} and H_{2}S the solution proved inactive to rabbits and also that after this extraction the acetic acid extract of the ash failed to kill. In other words, the sulphate of our body was insoluble in water. At times in passing H_{2}S into active solutions of the ashed plant freed from the acetic acid by evaporation the filtrate and likewise the precipitate were inactive. Noyes and Bray[174] have noted that if H_{2}S is passed into certain solutions in the presence of an oxydizing agent, such as ferric iron, H_{2}SO_{4} would be formed, which would throw any barium out of solution. In one blood-pressure record made with a dog (vagi nerves cut), a rise in blood pressure (a characteristic physiological action of barium) was seen to follow the intravenous injection of the aqueous extract of the plant, in spite of its normal acid reaction. Accidentally the writer found that Sprengel[175] had reported the presence of barium in _Astragalus exscapus_, a closely allied plant. Barium has also been found in the vegetable world by Scheele in 1788, and later by Eckard,[176] who found it in beech, while Forchhammer[177] proved it in birch, and Lutterkorth found it in the soil of the same area in which Eckard worked. Dworzak[178] noted the occurrence of traces of this element in wheat grown along the Nile, and Knop[179] found it in the soil. Doctor Balfour, of Khartum, Egypt, informed the writer that he knew of no cases in which this barium in wheat had produced poisoning. Hornberger[180] found barium both in the red beech grown in Germany and in the soil on which these trees grew. It has also been claimed that various marine plants may take up barium from the sea.[181]