48 ON THE ANIMAL FLTJI&3. 



animal matter, in the other animal fluicls, which he ex- 

 amined, was of one kind only, v\t. coagulable matter, 

 but not demonstrable by its most distinguishing property 

 on account of dissolution in a large proportion of water. 

 Ammonia not 2. Ammonia is not mentioned among the impregnating 

 roentione . ingredients. This is to me not surprising, for it is evidently 

 from my expaiments in so small a proportion as to be un- 

 discoverable in the quantities employed. If I could not 

 find by estimation half a grain weight of it in 7 or 8000 

 grains of animal matter, it was not likely to be rendered evi- 

 dent in 7 or 800 grains. 

 Sulphate of 3. Sulphate of potash. That a sulphate exists I perceived 



potash. evidence, and have accordingly inserted it among the saline 



matters in my published papers ; but that it is sulphate of 

 potash I apprehend will not be allowed to have been shown 

 by Dr. Marcet. 

 Phosphate of 4. Phosphates of lime, of iron, and of magnesia, are enu- 

 lime > u ? n » and merated in tlie memoir before me. Of phosphate of lime 

 there is good evidence, as I have set forth, and coincide in my 

 results with those of the author : as well as that there is 

 probably sulphate of magnesia: also, that there is iron; 

 but I was not able to infer, that it was in a state of phos- 

 phate, I only inserted it in my results as an oxide. 

 The colouring Although it is not essentially connected, I take this op- 

 blood'^kon P ortumt y °f referring to a- process, which I offer as evidence 

 against the common opinion, that the Colour of the blood 

 is owing to iroo. I have mentioned it in my lectures 

 during several past years, and it was published in the Edin- 

 burgh Medical and Surgical Journal, vol. VII, p. 124, for 

 January, 1811. I collected 110 grains of the red part in a 

 dried &tate, by repeated ablutions- from about 10000 grains, 

 or upwards of twenty ounces of blood. By burning in a 

 |>latina crucible, it afforded, in weight, two grains and a 

 balf of a half-fused broWn tasteless substance. By boiling 

 in muriatic acid a part was dissolved. This solution was 

 not styptic to the taste; it became blackish on adding 

 tincture of gall nut, and on adding prussiate of potash it 

 afforded a deep blue coloured precipitate, which did not 

 •yield by ignition, or calcination, above half a grain of 

 reddish brown powder. Is it then probable, that twenty 

 ounces of blood should derive their colour from half a grain 



of 



