32 



NATURE 



[A/aj 13, 1880 



FL/R THER OBSER VA TIONS ANDRESEA RCHES 

 ON FLEUSS'S SYSTEM OF DIVING AND 

 LIVING IN IRRESPIRABLE A TMOSPHEIiES ' 



■X/OU will find in NATURE, vol. xxi. p. 62, the experi- 

 ^ raents I made in relation to the process of living 

 under water by means of the Fleuss apparatus. I there 

 related what I had observed after Mr. Fleuss had 

 been under water at a very low temperature for the 

 period of an hour. A few days later I made another 

 observation on a different plan. I filled the large diving 

 bell at the Polytechnic with carbonic acid gas, displacing 

 every portion of air. I then let the bell go down ten 

 inches under the water, so as to put the gas under pressure, 

 and all the while I kept a stream of gas pouring into the 

 bell, and causing a constant bubbling of gas out of the 

 mouth of it into the water. This done, Mr. Fleuss put on 

 his dress and helmet and entered the bell. He sat in it 

 over the water for the period of twenty minutes, the 

 pressure and constant stream of gas being maintained. 

 At the end of twenty minutes I signalled to him to come 

 out, and had the bell brought round to the side of the 

 tank. He returned into the air quite unaffected. His 

 pulse, which was beating at 73° in the minute when he 

 went in, was at 68^ when he came out, and quite steady. 

 His temperature in the mouth, which was at 98-3° F. 

 ■when he went in, was at 97 'j' when he came out, and in 

 a few minutes was at its natural standard. He said he 

 had felt no oppression whatever, and would have remained 

 an hour in the gas if I had allowed him. 



While the diving-bell was still charged with a large 

 volume cf carbonic acid gas I got Mr. Fleuss to go into 

 it again, and then volatised into the bell vapour of amyl 

 hydride until I had made an utterly irrespirable atmo- 

 sphere from that vapour alone. In this way I formed an 

 atmosphere which closely resembled the atmosphere of 

 the mine charged with choke-damp, except that the 

 vapour I used is more determinate in its narcotising 

 action than choke-damp. In this mixed atmosphere, in 

 ■which a man unprotected would have been absolutely 

 unconscious in less than a minute, Mr. Fleuss remained 

 for twenty minutes. At that time he came out of the 

 bell in the most perfect condition, in a word, altogether 

 unaffected. 



The principle of the Fleuss system is very simple. 

 Within the helmet, which is of the usual shape of a diver's 

 helmet, there is a space equal to a quarter of a cubic foot 

 inclosed in metal. This space is charged with oxj-gen 

 under pressure, the compression giving a supply of the 

 gas sufficient to last for a period of five hours if neces- 

 sary. As a rule Mr. Fleuss charges for three hours under a 

 pressure of about eight atmospheres. This is his supply 

 of vital air. In the cuirass, which is the next part of the 

 apparatus to be described, he has two metal cases, one in 

 front, the other at the back. These cases are filled with 

 small pellets of porous india-rubber charged with caustic 

 soda. Over this surface of soda he can exhale his breath 

 with perfect freedom, and at the lower part of each case 

 he has a small trough under a perforated bottom, in 

 which the water of the breath, condensed in passing, is 

 caught. Lastly, he has a double-valved mouthpiece, 

 made almost exactly after the plan of the late Dr. SilDson's 

 chloroform mouthpiece, to which is attached a large 

 elastic artificial trachea, or windpipe. 



These arc the effective parts of the apparatus. The other 

 parts, common to the diver's dress, are the waterproof 

 jacket and leggings and weighted boots. 



In preparing for his work Mr. Fleuss proceeds as you 

 will see (for he will go step by step through the process 

 of assuming his dress). He first charges his helmet with 

 oxygen. He does this from one of Orchard's compressed 

 o.xygen bottles, measuring the pressure by a pressure- 



' Abstracted from lecture delivered to the Society of Arts on Thursday, 

 May 8. 



gauge. This ready, he puts on the cuirass and the water- 

 proof dress. Then he ties firmly over his mouth and 

 nostrils the double-valved mouthpiece, and connects the 

 free end of the artificial windpipe with a tube leading into 

 the soda-chamber in front of the cuirass. Finally he 

 assumes the helmet, and when that is on and closed he 

 is complete. 



The mode in which he lives in this closed dress is as 

 follows : — By a valvular opening he lets into the helmet 

 from the compressed store of oxygen a stream of oxygen, 

 which diffuses into the space between the helmet and 

 cuirass and his body — his breathing- or air-space. When 

 he inhales through the inouthpiece he draws in the oxygen 

 through the two side valves into his lungs. When he 

 exhales, those valves close, and so his exhaled breath 

 passes through the tube and over the soda in the soda- 

 chambers, and down the chamber in front along a con- 

 necting tube into the lower part of the chamber at the 

 back ; then, ascending through that chamber, it escapes 

 ill part into the helmet by a tube from the back chamber 

 near the shoulder. In its passage through these two 

 chambers aU the carbonic acid of the breath is fixed by 

 the soda, and most of the water is condensed in the 

 troughs. The return oxygen and the nitrogen of the 

 expired breath passes over free and enters the helmet, 

 where it meets and admixes, by diffusion, with the 

 oxygen which is admitted from the oxygen reservoir. 



Thus there is constantly being made within the dress a 

 fresh supply of air for respiration, while the product of 

 respiration and of animal combustion — carbonic acid — 

 whicli would be dangerous if it were not removed, is 

 remoxed and fixed by the soda. 



Mr. Fleuss relies on two practical indications for supply 

 of the oxygen from the reservoir. If he feels any undue 

 pressure on the drums of his ears he knows that there is 

 too much oxygen in the helmet. If he feels any sense of 

 suffoi;ation he knows that the oxygen is deficient. In the 

 first instance he stops the entrance of oxygen for a short 

 time ; in the second case he lets in a further supply. 



It must be admitted that this plan is not one that 

 ensures a due admixture of oxygen and of nitrogen 

 according to the atmospheric formula, and there can 

 be no doubt that he is always breathing, while in his 

 dress, an excess of oxygen. This fact opens up the 

 question once more of pure oxygen as a supporter of 

 natural hfe. 



In my experiments on this subject reported to the 

 British Association for the Advancement of Science in 

 i860, I showed that oxygen supplied in steady current 

 from a fresh source, and not breathed many times over 

 again, would support life readily enough for long periods 

 of time — extending in one experiment to three weeks — at 

 a medium temperature ; but that at a low temperature, 

 35'^ F., it became negative, so that animals went to sleep 

 in it and became cold ; while at a high temperature, 75°, 

 they became heated in it, underwent rapid wasting, and 

 ate voraciously. 



In another paper, published in 1S69, I tried to prove 

 that the use of nitrogen in the atmosphere is not to act 

 as a mere diluent and economiser, but as an equaliser of 

 the temperature, and so to make the combination of 

 oxygen with the blood and the tissues equable in the 

 different regions of the globe. 



Mr. Fleuss's experiments are in entire accord with these 

 views. He can live, with oxygen in excess, for long 

 periods in medium temperatures. In a cold temperature 

 his own heat goes down several degrees below the 

 standard. In a high temperature he would become over- 

 heated. But between a range of 35° F. on the one side 

 and 75° F. on the other he is, in my opinion, safe in his 

 closed oxygenated chamber. M'hether he can descend to 

 the same depths as other divers— say to 86 feet— and 

 remain there, has to be proved. Theoretically, he ought 

 to be able to do so, but in this field of inquiry he must 



