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a man, he again made a dog the subject of experiment ; and after he 

 had tied the pylorus, about three ounces of a mixture of tincture of 

 rhubarb with water were at intervals injected into his stomach. Upon 

 killing this dog, at the expiration of eight hours and a half, his blad- 

 der was found distended with urine highly tinctured with the rhubarb. 

 The spleen was turgid ; and, when cut through and examined by a 

 magnifying-glass, appeared to consist of two parts intermixed, but 

 very distinguishable from each other by their colour ; the one was 

 transparent, in the form of small circles or ovals, and surrounded by 

 a different structure, which was vascular, of a red colour, but of a 

 lighter hue than the substance of the liver. 



This spleen was immersed in water, and being cut into small 

 pieces, the water became discernibly impregnated with the rhubarb, 

 as was rendered manifest by the test of alkali. 



On the contrary, an equal portion of the liver of the same dog, 

 treated in the same way, gave no such colour to the water, but only 

 tinged it with blood of a red colour. Although fluids are thus found 

 to pass from the stomach to the spleen, the vessels by which they are 

 conveyed have not been detected, nor does Mr. Home entertain much 

 hope of such a discovery. 



On the Composition of the Compound Sulphuret from Huel Boys, and 

 an Account of its Crystals. By James Smithson, Esq. F.R.S. 

 Read January 28, 1808. [Phil. Trans. 1808, p. 55.] ^ 



Mr. Smithson gives a particular description of the form of the sul- 

 phuret of lead, antimony, and copper, because that which was laid 

 before the Society in 1804 appeared to him materially inaccurate 

 and imperfect; and he further offers some observations upon Mr. 

 Hatchett's experiments, which he deems essentially necessary to our 

 rightly understanding this substance, as well as many other chemical 

 compounds to which the same principles extend. 



The author conceives it not to be probable that this ore is a direct 

 quadruple combination of the three metals, lead, antimony, and cop- 

 per, with sulphur ; but thinks it much more credible that it consists 

 of the three sulphurets of these metals. 



On this presumption he makes experiments, to determine the pro- 

 portion of these sulphurets to each other; and since 10 grains of 

 galena produce 12 sulphate of lead, he thence infers the quantity 

 of galena indicated by 60*19 grains of sulphate of lead, obtained by 

 Mr. Hatchett. So also with respect to sulphate of antimony; 

 as 10 grains yield 11 of precipitate from muriatic acid by water, 

 he is enabled to determine the quantity of sulphuret of antimony, 

 corresponding to Mr. Hatchett's precipitate of 28' 64 grains. With 

 respect to sulphate of copper, his method is not so direct ; for as he 

 had none of this sulphuret on which to make experiments, he only 

 presumes that the remainder of the ore consists of this compound ; 

 and hence he obtains the following results : sulphuret of lead, 49' 7 ; 

 sulphuret of antimony, 29' 6 ; sulphuret of copper, 20' 7. 



From the hear agreement of these numbers with the simple pro- 



