Intelligence and Miscellaneous Articles. 385 



Hence, when I commenced my investigations, the existence of 

 copper in the blood appeared to be an accidental occurrence, void of 

 physiological importance ; which view derived support from the fact 

 that copper had been repeatedly found in the human bile, in gall- 

 stones, and in the liver, which especially accumulates metals foreign 

 and injurious to the body. 



In my experiments, about 800 to 1500 grains of the muscular 

 substances and other soft parts of vertebrate animals, and 15 to 250 

 grains of those of the invertebrate animals were used. The substances, 

 which were coarsely minced when necessary, were incinerated in a 

 platinum dish over a Bunsen's gas-burner. The reduction to ash is 

 difficult and tedious, but indispensable for the certain detection of the 

 copper ; for so long as unburnt carbon is present, this retains not 

 only the copper but also the iron, so that these metals are not acted 

 upon by the muriatic acid for instance. The combustion of the car- 

 bon may, however, be promoted by exhaustion with boiling water, 

 which removes the soluble salts. The filtered solution contains 

 phosphoric acid, alkaline chlorides and sulphurets, but no copper, and 

 may therefore be disregarded. The filter with the carbon is dried, 

 the latter separated from the filter, and perfectly incinerated. The 

 copper exists in the ash as oxide. It is moistened with a little hy- 

 drochloric acid, gently warmed, a little water added, filtered, and 

 washed. The perfectly clear liquid is treated with solution of sul- 

 phuretted hydrogen. If it becomes brownish, or even yellowish, we 

 may be sure that copper is present ; but it frequently becomes blackish 

 brown or even brownish black. The liquid is set aside in a warm 

 place for some hours, when a brown or black deposit is formed, 

 which is filtered and washed. The very small filter with the preci- 

 pitate is dried and incinerated. The ash warmed with a drop or two 

 of hydrochloric acid gives with ammonia a blue solution. More con- 

 clusive evidence is afforded by reducing the ash on charcoal with 

 soda by the blowpipe, triturating the incinerated mass in an agate 

 mortar with water, and pouring off the carbonaceous particles, when 

 spangles of copper are left behind. Not unfrequently the spangles 

 are metallic grey or yellowish grey instead of red ; in this case lead 

 is precipitated and reduced with the copper, and obscures its red 

 colour. 



Copper was detected in the following classes of animals : — 

 Mammalia. — In the human urine and faeces with lead — and hence, 

 as was found by experiment, in the flesh and blood. In the sto- 

 mach and intestines of a European and of a Canadian lynx copper 

 was found. Also in those of the Lesser and Red Coatimondi (Nasua 

 mexicana and rufa); in those of the Chetah (Cynailurus guttata) ; 

 those of Canis cancrivorus ; repeatedly in horseflesh, and the flesh of 

 the ox. 



To determine whether the copper existed in the soluble portions 

 of ox-flesh or in the insoluble tissues, Liebig's extract of flesh was 

 used ; and in this it was detected, as also in boiled ox-flesh. 



Birds. — Copper was found in the flesh of the breast of the teal ; 

 in the yelk of a hen's egg, as also in the white, but in far less 

 quantity. 



Phil. Mag. S. 4. Vol. 30. No. 204. Nov. 1865. 2 C 



