The Optical Magic Lantern Journal (February 1897)

The Optical Magic Lantern Journal and Photographic Enlarger. 50 of acetylene. The conclusion was that acetylene is but very slightly poisonous. Two other experimenters, Messrs. Malvoz and Crismer, made similar experiments with results agreeing with those of Mr. Brociner, viz., acetylene is not poisonous. Mr. Brociner made the following deductions : — A. Blood dissolves about + of its volume of acetylene. B. Spectroscopic examination of blood mixed with acetylene reveals nothing special; this solution behaves exactly like normal oxygenated blood, and is similarly reduced with equal speed under the influence of hydrosulphate of ammonia. C. Under the influence of a vacuum, blood loses the acetylene ; most of the gas is evolved cold, but to extract the totality the temperature must be raised to 60° C. Rodents, rabbits, and guinea-pigs resist the effects of oxide of carbon much better than carnivorous animals. Thus », of oxide of carbon in the air kills a rabbit in 1 hour, and ot, a dog. Some experiments were made to ascertain whether such is the case with acetylene, and a mixture of 40 per cent. of acetylene (as stated in our ‘‘ Notes,’ in September Journal, page 188) killed a dog in 51 minutes, also a pigeon in 1 hour and 21 minutes. From which Dr. Gréhant concludes that acetylene is about as poisonous as carbonic acid, which kills animals in mixtures of 40 to 50 per cent., and much less poisonous than oxide of carbon, and consequently coal gas. In practice, one will very rarely be exposed to inhale a mixture of air and acetylene at 30 to 40 per cent.; much slighter quantities, however, may be injurious by decreasing the relative proportion of oxygen in the air, exerting, perhaps, an unfavourable influence on normal exhalation of carbonic acid by the lungs. It is chiefly by explosive mixtures which acetylene forms with air that this greatly carburetted gas may cause serious accidents. It is recommended that’ persons who have inhaled acetylene, quickly breathe pure air; thus it is rapidly removed from the organism. Acetylene is much less poisonous than oxide of carbon, and this fact can be demonstrated by an experiment which demonstrates at the same time that acetylene is dissolved by the blood and that the oxide of carbon is fixed. As an experiment, a mixture of 20 per cent. of acetylene, air and oxygen was composed, containing 28°8 per cent. of oxygen, and added ,3, of pure oxide of carbon to the mixture. After inhaling these gases for 30 minutes, a dog experimented with had respired 70 litres; the animal was then bled, and 20 cubic centimetres of the arterial blood was injected into a receiver main 31 ! | combustible gas. ' a spiral of platinum, maintained at a red heat tained at 37°C.; after pumping out the air it was found to contain Gas Potash .. 16-4 per cent. cubic centimetres. 6-4 ”» ” ” Carbonic acid 10 rn is ” The remaining gas, 6-4 cubic centimetres, was run into the gas indicator, and 8:6 cubic centimetres of acetylene were obtained per cent. of blood. In the same receiver, which contained bright red blood (oxycarbonated), was placed 40 cubic centimetres of acetic acid at 8°C., and the water boiled in a water bath. Gas obtained 3:3 cubic centimetres’ Potash .. ‘3 is ” This gaseous residuum mixed with air gave in the indicator a reduction of 13-7 divisions, due to the presence of oxide of carbon, which corresponds to 1:8 cubic centimetres of this gas, the volume of which in 100 cubic centimetres of of blood was 9 cubic centimetres. Thus, in acase of poisoning by a mixture of acetylene and oxide of carbon it was possible to separate the first gas dissolved in the plasma of the blood from the second combined with hemoglobin. Such different proportions as 20 per cent. of acetylene and 0:2 per cent. of oxide of carbon, which are as 100 to 1, introduced about the same volumes of the two gases into the blood; 8-6 cubic centimetres of acetylene and 9 of oxide of carbon. II. CompLeTe ComBusTION or ACETYLENE. ANALYSIS OF Proptcts oF ComBusTion.—To collect the products of combustion of acetylene, on a Manchester burner giving a very bright flame, a vertical metal cylinder ,;connected with a cold water refrigerator and a gasometer was placed; all the products of combustion were conveyed with air into the gasometer, and 80 litres of gas were collected in two minutes. Analysis of the gases was made by baryta water, and showed 33:7 cubic centimetres of carbonic acid in 1,700 cubic centimetres of gas, or 1,468 cubic centimeters in two minutes. Two eudiometric analyses made gave for oxygen 18-59 and 18°57; the volume of oxygen consumed was equal to 1,786 cubic centimetres. The proportion °° equals 0:82. Now weare aware that a volume of pure acetylene consumes 2°5 volumes of oxygen, and gives 2 volumes of carbonic acid; the proportion °° equals 0°8. The numbers found indicate then the eudiometric character of acetylene in the Manchester burner. Direct researches. were made to ascertain whether combustion of acetylene engenders Into a glass bulb containing