June 12, 1885.] 



♦ KNOWLEDGE ♦ 



497 



small compass. By plunging a piece of freshly-biirnt char- 

 coal into mercury while still red hot, ami passing this when 

 cooled into a jar of gas standing over mercury, the rise of 

 the mercury measures the volume of gas absorbed by the 

 charcoaL 



Boxwood chiircoal, thus treated, has been found to 

 absorb 90 times its own bulk of ammonia, ^r> of hydro- 

 chloric acid, Gf) sulphurous acid, 55 sulphuretted hydrogen, 

 40 protoxide of nitrogen, 35 carbonic acid, 9t carbonic 

 oxide, 9 2 oxygen, 7 -5 nitrogen, 5 carburetted hy Jrogen, 

 1 •' hydrogen. In this case the ammonia and hydrochloric 

 acid are condensed into a smaller bulk than they occupy 

 when made liquid by mechanical pressure. 



The adhesion of hydrogen to metals, and consequent 

 condensation within tlieir pores, is still more remarkable, 

 especially as these pores require optical assistance to render 

 them visible. Thus Graham pumj)ed out of a piece of 

 meteoric iron 2 -So times its own bulk of gases, of which 

 86 per cent, was hydrogen. This " occlusion" of hydrogen 

 by some metals, notably by palladium, solidities the hydro- 

 gen into metallic hydrogenium which forms an alloy with 

 the palladium. The condensation in this case is enormous, 

 the volume of hydrogen absorbed bj' the palladium being, 

 under certain conditions, being 980 times greater than that 

 of the palladium itself, the bulk of the solid increasing in 

 accordance with the theory that the hydrogen has become 

 a solid metal, and is alloyed with the palladium, and the 

 properties of the solid are modified accordingly. The 

 hydrogenium may be separated in its original form of 

 gaseous hydrogen by simply heating the alloy. 



We are still without data for determining the quantity 

 of gas which is condensed upon the fibres of natural and 

 artificial clothing material, and of its variation under 

 difierent conditions ; so far as I am able to learn, this 

 subject has dropped out of sight since the publication of 

 Rumford's essays. Modern physiologists have devoted 

 themselves very industriously to the splitting of hairs and 

 the examination of their microscopic structure and morpho- 

 logical relations, and generally to any and every other 

 subject that is far fetched and pedantic, while they have 

 sadly neglected those vulgar practical researches to which 

 Rumford devoted himself. Now that I am upon thLs very 

 practical subject of clothing, I find myself compelled to 

 repeat what I have already said in reference to my previous 

 subject of cookery, viz., that the whole amount which the 

 science of the current century has directly added to the 

 work of Rumford is so small as to be simply contemptible. 



Certain irreverent outsiders reviewing the selection of can- 

 didates for Fellowship in the Royal Society have been 

 wicked enough to describe that venerable association as an 

 advertising agency for fashionable physicians. I will not 

 express my own opinion on the general merits of its recent 

 " Transactions," but must say that I am surpri.^^ed at the 

 infinitesimal amount of work that has been done by these 

 numerous medical Fellows in following up the researches of 

 Rumford, and the fact, clearly indicated by their published 

 works, that they are generally ignorant of his contriVjutions 

 to the tnily " Philosophical Transactions " of the Society. 

 This, in spite of the fact that he left Bavaria, came to 

 England, and resided in Brompton-road for the express 

 purpose of republishing his useful scientific papers in con- 

 venient form for reference, which he did between 1790 

 and 1802. He also founded the Royal Institution for the 

 purpose of disseminating a knowledge of these discoveries 

 and inventions, and encouraging others to make similar 

 researches in the region of practical philosophy. 



In spite of this, his work died with him. Speculators 

 would not patent his invention, nor pedants glorify them- 

 selves by further investigation of such vulgar subjects, and 



thus I find myself compelled to take them up just where 

 he left them nearly a hundred years ago. He, by his 

 original and unaided researches, showed that the natural 

 clothing material of the warm-blooded animals that live out 

 of water is practically a stratum of air held captive by the 

 fibres of their hair or feathers, and that our artificial clothing 

 is, or should be, so constructed as to provide us with a 

 similar en\elope, which, while it resists the transniiesion of 

 heat from our bodies in the manner he explained, does not 

 prevent the exhalations of the skin from passing through it. 



These original experiments of Rumford were necessarily 

 crude ; he had not the instrumental advantages, the well- 

 appointed laboratory, and skilled assistants that are now 

 available ; his researches demand repetition, correction, and 

 extension, but have not received them. This applies not 

 only to that part of the subject I have already treated — 

 the relations of clothing to the temperature of the 

 body, but also to another function of clothing yet to be 

 treated — viz., the absorption of cutaneous exhalations. 

 Here again I find that the only quantitiitive researches 

 directly bearing on the subject and worth notice are 

 those by Rumford. 



Before taking up these, I must add tliat the import of 

 his crude experiments has been increased by what we 

 have subsequently learned in other fields of research, 

 though their connection does not appear to have been 

 noted. 



Rumford only regarded the protective effectiveness of air 

 in connection with non-conduction of heat and the inter- 

 ference of the fibres with its convective movements. The 

 researches of Melloni and Tyndall on radiant heat have 

 subsequently taught us that air, when saturated with the 

 aqueous vapour, is an effective shield to radiation ; that it 

 is almost impenetrable to the radiations of obscure heat, 

 such as those from the body. The law of exchanges, now so 

 firmly established, further supplies us with the deduction 

 that each particular hair is perpetually radiating heat 

 towards the body ; the more it receives from the body the 

 more it returns towards it, and to its fellow-hairs or fibres. 

 The efiicacy of this is, however, practically minimised to a 

 barely appreciable quantity by the resistance to obscure 

 radiation, due to vapour exhaled from the skin, and thus 

 we come again to the stagnated atmospheric envelope as the 

 true clothing material. 



I must now consider the relations of clothing to the 

 cutaneous exhalations. We must always remember that 

 these exhalations have the character of excretions — are 

 poisons if returned inwards by absorption or otherwise. 

 The enjoyment of full health demands that they shall be 

 removed as speedily as possible. There are two kinds 

 of personal dirtiness and two kinds of personal clean- 

 liness ; there is dirt that comes from without and 

 dirt that comes from within. Those silly women who 

 have imbibed the Parisian notion that soap and water 

 spoil the complexion, and who, therefore, only dab and 

 smear their skin with toilet vinegar or other cosmetics, 

 have on a daily average dirtier faces than the blacksmith 

 who at the end of his day's work indulges in a vigorous 

 soaping, a copious swilling, and a cool, hearty dip in a big 

 bucket of fresh water. The colourless excreted dirt that 

 she plasters back is far more mischievous and more truly 

 dirty than the carbon flocculi that modify the blacksmith's 

 complexion. 



The practical and philosophical question which tliis part 

 of my subject suggests is : Whether clothing materials 

 differ in their powers of absorbing the cutaneous exli;da- 

 tions ; if so, which are the most effective, and what are the 

 relations of this function to that of confining air, .and there- 

 Vjy maintaining the temperature of the body 1 If th'^'^e two 



