August 3, 191 1] 



NATURE 



i57 



where this does not fit the wearer a g 1 deal of 



l i rom the pressure. 

 Physiological observations on men wearing different forms 

 ipparatus wen carried out ■ luring; this investigation, as 

 it v\ ;!-, clear!} important to discovei whether the wearing 

 of the apparatus and the doing of hard work in them 

 for upwards of two hours at a time was or was not in- 

 jurious to the volunteers. The investigations were con- 

 ducted in the experimental mine attached to the mining 

 department of the University of Birmingham. This repre- 

 sents on a reduced scale all the typical workings found in 

 a mini-, and it is so constructed that it can be filled with 

 smoke and its atmosphere made irrespirable, or can have 

 steam driven into it so .o to saturate the air, but leave it 

 spirable. 



The men, then, worked in three sorts of atmospheres : — 

 (11 With air at the ordinary temperature. 

 (-•I Hot, moist, and irrespirable atmospheres, in which 

 1I1- wel bulb w a, about So F. 



(3) Hot. moist, but respirable atmospheres with the wet 

 bull) about 90° F. 



The men varied in age from twenty-five to fifty, in 

 height from 5 feet 7 inches to 6 feel 6 inches, and in \\ . :ighl 

 from about 55 to 89 kilos. The men were weighed naked 

 before and after a test, and the gross loss of weight so 

 ascertained. The losses in weight varied from such figures 

 as .'20 grams to 1700 grams in two hours ; they bore no 

 definite relationship to the body-weight in any given casi 



The loss of carbonic acid gas was ascertained by weigh- 

 ing tlie 1 egenei ators, absi >i bi nts, before and after the 

 experiment, in weight giving the moist 



carbonic gas absorbed. Such figures as 527 grams of CO, 

 in 30 minutes and iSo-5 grams in 130 minutes were 

 obtained. The C0 2 excreted depends on such a large 

 numbei "1 conditions mass 1 I body, temperature, tempera- 

 ment, amount of work to be done, nature of food, light or 

 dark surroundings, &c. — that it is best to express it pet- 

 kilo, of body-weight per hour, and when this is done it 

 is en that the weight of moist CO . excreted is repre- 

 sented by a figure not greater than 2. and rarehj so low 

 as 0-5 gram. In other words, the amount of carbonic 

 acid gas eliminated in unit time P'V unit of tissue is ver} 

 much the same for all the men (12) subjected to the same 

 external condition. There was a remarkable uniformity in 

 the average weights of thi gas all the four 



types of apparatus worn in rotation by all the experi- 

 menters, thus: — in the Fleuss, 1-25; Meco, 1-28; Weg, 

 0-86 ; Draeger, 1-14. 



The observations on the pulse did not elicit anything 

 very interesting, for, as was to be expected, the heart- 

 beat was markedly accelerated. The minimum number of 

 beats added per minute was 16, the highest 58, but it was 

 factory to know that in all eases the heart had re- 

 turned to its normal within fifteen to twenty minutes after 

 the tesl was slopped. 



A- regards the respiration, nothing more than a physio- 

 logical hyperpncea was observed in any case; true dyspnoea 

 was never seen, even at the end of two hours' hard work- 

 ing. No bad effects of the inhalation of pure oxygen as 

 d by some physiologists in the case of the lower 

 animals were noticed. The very absence of dyspnoea under 

 conditions of oxygen deficiency may become a danger. It 

 is usual for men to suffer from violent and embarrassed 

 breathing when their supply of oxygen begins to run out, 

 but a small proportion, about 10 per cent., appear to be 

 seized with cardiac syncope instead of dyspnoea. The 

 importance of this is that, suppose such a man is the last 

 of a team, then, if his oxygen runs short, he simply falls 

 down unconscious without giving any warning to his com- 

 panions. He may be left behind in the smoke, as he is 

 unable to call out to them that anything is wrong. The 

 members of the committee, in view of an accident of this 

 kind, point old the danger of allowing only two men to 

 form a rescue-team and - nter an irrespirable zone. The 

 commit! iee was greatly struck with the enervating effects 

 of moist heat on the workers. The report contains the 

 following sentence ; — •• VVe were impressed by the rapid 

 onset of fatigue, particularly mental, in very hot and moist 

 atmospheres (group 3). When the wet bulb is higher than 

 $5° F. or so, a man, especially if he has hard work to do. 

 is overcome by irresistible lassitude. He becomes irritable. 



no. 2179, vol. 87] 



as well as indisposed to mental exertion. We think this 

 partial mental enfeeblement a fact of some consequence, 

 inasmuch as a person fatigued by hard work in a n - 

 apparatus in a hot and moist atmosphere might, in 30m 

 situation requiring promptness of decision, coolness of 

 judgment, the accurate recollecting ol instructions, plan-. 

 &c, not prove himself equal to the emergency. 



The heat developed in the regenerators was such that 



the men had the skin of the back burnt on mori I 



occasion. Temperatures of more than 200° F. were 

 tered in the regenerators, and 135 F. was attained by the 

 outside of the bag ol thi Fleuss. Undoubtedly one of the 

 sources of this heat is that from the chemical combina- 

 tion (2Na.OH+CO, = Na„.CO +11. Oi which i- slowlj dis- 

 sipated in the hot atmosphere. The last point of interesl 

 is that the temperature of the circulating oxygen in hot 

 atmospheres became so high as to burn the throat. Now 

 this temperature was rarely higher than too !■'.. and yet 

 it produced great discomfort, while we know that thi ai 

 in a Turkish bath can be breathed without discomfort 

 when the temperature is as high as 200 F. The diffi n 

 is that in the- rescue apparatus it becomes - u 

 whereas in the Turkish bath it is kept as dry as possible. 

 The dry, although hot, air allows the water to evaporati 

 from the mucuds membrane, and so carry off heal 

 latent state; but the saturated air circulating in the 

 apparatus permits of no evaporation, and consequent!} ol 

 no ini responding loss of heat. 



At an honorary degree celebration of the FJniversit; 

 of Birmingham on Thursday, July 27, a numbi 

 distinguished persons received honorary degrees in coi 

 tion with the visit of the British Medical Association, and 

 the following speeches were made by the principal (Sir 

 Oliver Lodge) in presenting them to the Vice-Chancellor :— 



The president of the Royal College of Physicians of 

 Edinburgh, physician to the Royal Edinburgh Infirmary, 

 lecturer on medicine in the Extra Academical School ol 

 .Medicine, anil reader of the address in medicine at thi 



I 'it meeting of the British Medical Association, Dr. 



Bramwell is the author of many splendid works on med 

 subjei Is, in particular of a monumental atlas of clinical 

 medicine, which have made his name known all over tin 

 world and will perpetuate his memory. An indefatigabl 

 worker, .a brilliant clinical teacher, and one of tin- best 

 known and esteemed physicians in the British Island-, I 

 present for the honorar} degree of Doctor of Laws 

 Byrom Bramwell. 



The city of Birmingham has for man} years bel 

 strongly in local self-government and strenuous civic 

 administration. Recently it has assumed enlarged re- 

 sponsibility, and in this expansion it grateful!) acknow- 

 ledges the assistance and high encouragement it has 

 received from the President of the Local Government Board 

 a man who, during his term of office, has consistently 

 shown active and practical and powerful sympathy with 

 the struggling period of more than one expanding or 

 federating municipal enterprise ; while the future housing 

 of many a community will benefit by his energetic insist- 

 ence on foresight in planning and thoroughness in drains. 



We of this University, closely connected as wi an 

 with the city, wish to join in expressing to him our cordial 

 ■; 1 feeling and gratitude. 



Fortunately the present occasion -iv.-s to this feeling 

 an opportunity of expression quite apart from any kind of 

 political or social controversy. For the medical faculty 

 represented to the Senate that in his capacity as head of 

 the department which is concerned with the sanitary 

 administration of this country, the Member for Battersea 

 has constantly cooperated with the medical profession in 

 their efforts to improve public health and has given his 

 powerful assistance to those municipalities which are try- 

 ing to ameliorate the sanitary conditions of the areas under 

 their control. A man of exceptional vigour and of health, 

 both in mind and body, which he devotes without stint to 

 the service of the community. I present to you for the 

 honorary degree of Doctor of Laws 



The Right Hon. John Burns. 



