CARBON MONOXIDE. 
§ 49-1 
81 
bright red, and the blood exhibited the spectrum of carbon monoxide 
haemoglobin. 
Domenic Mirto made some, experiments of a like nature and 
concluded— 
1. That in post-mortem diffusion the anterior part of the liver 
was rich in carbon monoxide, but in poisoning the gas is 
equally diffused. 
2. In post-mortem diffusion the pia mater scarcely ever contains 
carbon monoxide, the choroid plexus never. 
3. The deep parts of the body contain less than the superficial in 
the case of diffusion ; the reverse is the case in poisoning. 
Straussmann and Schulz, in a research on seven adult bodies, fairly 
well agree with Mirto, save that they believe that, given sufficient 
time, there is no part of the body into which carbon monoxide will not 
penetrate. 
§ 49. Detection of Carbon Monoxide. —It may often be necessary to 
detect carbon monoxide in air and to estimate its amount. The detection 
in air, if the carbon monoxide is in any quantity, is easy enough ; but 
traces of carbon monoxide are difficult. Where amounts of carbon 
monoxide in air from a half per cent, upwards are reasonably presumed to 
exist, the air is measured in a gas-measuring apparatus and passed into an 
absorption pipette charged with alkaline pyrogallic acid, and when all the 
oxygen has been abstracted, then the residual nitrogen and gases are 
submitted to an ammoniacal solution of cuprous chloride. 
The solution of cuprous chloride is prepared by dissolving 10-3 grms. 
of copper oxide in 150 c.c. of strong hydrochloric acid and filling the flask 
with copper turnings ; the copper reduces the cupric chloride to cuprous 
chloride ; the end of the reduction is known by the solution becoming 
colourless. The colourless acid solution is poured into some 1500 c.c. of 
water, and the cuprous chloride settles to the bottom as a precipitate. 
The supernatant fluid is poured off as completely as possible and the 
precipitate washed into a quarter-litre flask, with 100 to 150 c.c of dis¬ 
tilled water and ammonia led into the solution until it becomes of a pale 
blue colour. The solution is made up to 200 c.c., so as to contain about 
7-3 grms. per cent, of cuprous chloride. 
Such a solution is an absorbent of carbon monoxide ; it also absorbs 
ethylene and acetylene. 
A solution of cuprous chloride which has absorbed CO gives it up on 
being treated with potassic bichromate and acid. It has been proposed 
by Wanklyn to deprive large quantities of air of oxygen, then to absorb 
any carbon monoxide present with cuprous chloride, and, lastly, to free the 
cuprous chloride from the last gas by treatment with acid bichromate, 
so as to be able to study the properties of a small quantity of pure gas. 
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