338 



NA TURE 



[February 8, 1900 



bein thought that it was a derivative of nitrogen, viz. 

 that the latter was "a compound consisting of ozone 

 and hydrogen" (letter of April 19, 1844). In 1853 he 

 tells Faraday that the nature of ozone appeared to have 

 been settled in Bunsen's laboratory: "that there is one 

 sort of ozone containing nothing but oxygen, and another 

 that contains some hydrogen " (p. 213). By 1854 he had 

 fully recognised that oxygen could exist in two different 

 states, and this leads him to some further speculations 

 on electrolysis, thermolysis and photolysis, which are 

 well worthy of consideration even at the present time. 



Students of the history of chemistry are, of course, 

 familiar with all the points raised in the course of 

 Schonbein's labours on ozone : but the personal recital 

 of the discoverer's views, hopes, experimental results, 

 and his refutation of the criticisms of other chemists 

 will be found most instructive reading. He unbosoms 

 himself freely to Faraday, in whom he found that sym- 

 pathetic spirit which is so powerful an aid to scientific 

 progress when exercised between co-workers whose 

 greatness of mind and disposition exalts them above the 

 level of all professional rivalry or petty jealousy. 



The discovery of gun-cotton is heralded in 1846, when 

 nitrated cellulose is introduced to Faraday with the 

 statement : — 



"To give you an idea of what may be made out of 

 vegetable fibre, I send you a specimen of a transparent 

 substance which I have prepared out of common paper. 

 This matter is capable of being shaped out into all sorts 

 of things and forms, and I have made from it a number 

 of beautiful vessels." . . . 



" There is another point about which I take the liberty 

 to ask your kind advice. I am enabled to prepare in any 

 quantity a matter which, next gunpowder, must be 

 regarded as the most combustible substance known. So 

 inflanmiable is that matter, that on being brought in 

 contact with the slightest spark it will instantly be set 

 on fire, leaving hardly any trace of ashes ; and if the 

 combustion be caused within closed vessels, a violent 

 explosion takes place. . . . 



" A substance of that description seems to be appli- 

 cable to many purposes of daily life, and I should think 

 that it might advantageously be used as a powerful means 

 of defence and attack. Indeed, the congrevian rockets 

 can hardly be more combustible than my prepared cotton 

 is. What shall I do with that matter.? Shall I offer it 

 to your Government? I have enclosed a little bit of 

 thnt really frightful body, and you may easily convince 

 yourself of the correctness of my statements regarding 

 its properties." 



Human nature in 1846 appears to have been pretty 

 much the same as it is now when a "utilitarian " scien- 

 tific discovery is made ; and in another letter of the same 

 year he confides to Faraday, that while his knowledge of 

 the world has been vastly increased by his experience, his 

 " esteem for mankind has not grown in the same ratio " 

 He adds: - 



" I could tell you a great many things of an incredible 

 description, but I will not trouble you with detailing facts 

 which I should like never to have become acquainted 

 with myself. So much, however, I must say, that by the 

 occurrences alluded to, my temper, which is usually not 

 much liable to be ruffled, and the placidity of my mind 

 have been suffering these many months" (p. 165). 



But apart from these capital discoveries with which 

 Schonbein's name will be always linked, and which are 

 NO. 1580. VOL. 61 J 



now part and parcel of our modern science, some of the 

 bye-products of that active mind are perfect marvels of 

 scientific intuitiveness. A few of these collateral sug- 

 gestions have been noted in reading through the corre- 

 spondence, and readers of Nature will be interested in 

 having their attention called to some of the more striking 

 passages. Compare, for instance, the present views on 

 the nature of electricity with the statement written to 

 Faraday in 1839 : — 



" It appears to me that what we call static electricity is 

 only a state of tendency of something to move in certain 

 direction, and thatturrent-electricity is the actual motion 

 of that something. That motion must not be considered 

 as one of weighty particles, but as a motion of something 

 that is not affected by gravity ; as a peculiar motion of 

 the ether, if you like. .A.ccording to these hypothetical 

 views, we can easily conceive how a vibratory motion 

 might he propagated through a space, or medium, empty 

 of weighty particles, but filled up with some imponder- 

 able matter which is capable of being brought into a 

 moving state. The only thing difficult to conceive is the 

 relation of that imponderable agency to the weighty 

 particles in their natural and excited condition ; that is to 

 say, the way in which both are acting upon each other. 

 It is possible that a state of tendency to motion maybe 

 brought about in ether only by a peculiar action of pon- 

 derable particles upon that fluid, and that consequently ' 

 such a state cannot exist in it without the presence or 

 agency of matter, whilst moving ether of itself has the 

 power to impart motion to ether being at rest " (p. 71). 



The question of the colour of oxy-compounds appears ,, 

 to have directed Schonbein's attention towards the sub- 

 ject of colour in general. In 1852 he penned this most 

 significant statement : — 



" I cannot help thinking that the colours of substances,, 

 which up to this present moment have been very slightly 

 treated (in a chemical point of view), will one day become 

 highly impohant to chemical science, and be rendered 

 the means to discover the most delicate and interesting 

 changes taking place in the chemical condition of bodies. 

 In more than one respect the colour of bodies may be 

 considered the most obvious signatura return, as the 

 revealer of the most wonderful actions going on in the 

 innermost recesses of substances, as the indicator of the 

 most elementary functions of what we call ponderable 

 matter." 



The letter from which the above passage is quoted 

 contains remarks which — to put the case with the least 

 disparagement to the memory of their writer — show that 

 the then newly developing science of organic chemistry 

 found very little to commend it to Schonbein's mind. 

 Faraday echoes his sentiments in his reply to this letter, 

 in which he says : — 



"You are very amusing with your criticisms on organic 

 chemistry. I hope that in due time the chemists will 

 justify their proceedings by some large generalisations 

 deduced from the infinity of results which they have col- 

 lected. For me, I am left hopelessly behind ; and I will 

 acknowledge to you that, through my bad memory, organic 

 chemistry is to me a sealed book." 



Again and again does Schonbein declare his attitude 

 towards this branch of science, not only in his letters to 

 Faraday, but also to other contemporary men of science. 

 In a letter to Faraday, written in 1854, he speaks of 

 "cook-like chymists, who are brewing on and on their 

 liquors and puddings without paying much attention to 

 the conditions of the primary matters they are continually 



