2l8 



NATURE 



{Jan. 17, 1878 



FRANKLAND'S RESEARCHES IN CHEMISTR V 



Experimetital Researches in Pure, Applied, and Physical 

 Chemistry. By E. Frankland, Ph.D., D.C.L., F.R.S. 

 &c. (London : Joha Van Voorst, Paternoster Row.) 



THE numerous and valuable investigations of Dr. 

 Frankland in general chemistry are so well known, 

 that chemists will doubtless regard the issue of his 

 collected researches with lively satisfaction, partly on 

 account of the ease with which the various memoirs can 

 be referred to in the fine volume before us, but chiefly 

 because the work is likely to prove of special value as an 

 aid in the higher education of chemical students. 



Any criticisms of the statements of fact or of theory 

 contained in such a set of " collected researches " would be 

 so clearly out of place in Nature, that we need offer no 

 apology for dealing with the work before us^from a general 

 rather than from a technical point of view. Indeed, almost 

 all the matter contained in the volume has long been the 

 common property of all engaged in the pursuit of chemistry, 

 while the manner in which the investigations are presented 

 to the reader is alone new. The chief interest of the work 

 as a whole is due to the fortunate circumstance that its 

 varied contents have been grouped by the distinguished 

 author of the researches, who has bound them together 

 with a species of commentary that enables the reader 

 clearly to appreciate the relations of the parts in each 

 line of inquiry, and to obtain such glimpses into the 

 working of the mind of the investigator as the study of 

 formal papers can rarely afiford. 



The subject-matter of this fine volume of rather more 

 than 1,000 pages is conveniently divided into three 

 sections. Section I, contains the author's researches in 

 Pure Chemistry ; Section II., those in Applied Chemistry ; 

 and Section III,, the investigations that belong to the 

 physical side of the science. 



Section I. is fitly introduced by a chapter on the 

 peculiar system of notation now employed by Dr. Frank, 

 land. This introduction was rendered necessary by the 

 translation of the older formulae employed in the earlier 

 memoirs into those more recently adopted by the author. 

 Although Dr. Frankland's system of notation is un- 

 doubtedly interesting, we fear that its use throughout the 

 volume will detract from the educational value of the 

 work in the eyes of those chemists who think that the 

 expressions in common use can be made to serve the 

 same purposes as those employed in the South Kensington 

 School. 



As the work stands, 'however, the chapter in question 

 is useful in its place, and it may induce some chemists to 

 adopt the author's system who have hitherto held aloof 

 from it. 



The first of the series of researches given is that on the 

 transformation of cyanogen into oxatyl. This well- 

 known inquiry was carried on in conjunction with Dr. 

 Kolbe at a time when the investigation of the then recog- 

 nised "compound radicles " had commenced to excite much 

 interest, more especially in view of Liebig's recently pro- 

 pounded theory of conjugated compounds. The inves- 

 tigation led to the highly important conclusions that most 

 of the organic acids owe their acidity to the presence of 

 the group CO OH (the semi-molecule of oxatyl), and that 

 their basicity depends on the number of these groups 



contained within their molecules j while it was shown 

 that the synthesis of many acids of the acetic series 

 could be effected by the conversion of the cyanogen of 

 alcoholic cyanides into the oxatyl semi-molecule by the 

 action of alkalies. This research has since borne rich 

 fruit, and it seems to have led, almost directly, to the 

 most important of the author's discoveries, namely, to the 

 isolation of the alcohol radicles by the action of zinc on 

 iodides of radicles containing half the number of atoms 

 of carbon. Although this research was one of the most 

 important contributions to synthetic chemistry that had 

 then been made, its full value was not understood till M. 

 Wurtz completed Dr Frankland's work by the discovery 

 of methyl-ethyl, and other mixed radicles, which he pre- 

 pared by the action of zinc on mixtures of alcoholic 

 iodides, thus filling up the gaps in Frankland's list, and 

 rendering the method a general one for ascending the 

 homologous series. 



In the course of experiments on the action of zinc on 

 the iodides of alcohol radicles, Frankland made the 

 remarkable discovery that the metal can unite directly 

 with the alcohol radicles and form the curious and inter- 

 esting compounds now termed " organo-metallic," of which 

 zinc-methyl and zinc-ethyl are those most commonly 

 known. The author says " zinc-methyl and zinc-ethyl 

 were the first of these bodies with which I became 

 acquainted ; they were discovered on July 12, 1849, i'^ the 

 laboratory of Prof. Bunsen at Marburg, during my work 

 on the isolation of the organic radicles. After making 

 the reaction for the isolation of methyl by digesting 

 methylic iodide with zinc, and after discharging the 

 gases, I cut off the upper part of the tube in order 

 to try the action of water upon the solid residue. 

 On pouring a few drops of water on this residue a 

 greenish blue flame several feet long shot out of the tube, 

 causing great excitement amongst those present. Prof. 

 Bunsen, who had sufifered from arsenical poisoning during 

 his researches on cacodyl, suggested that the spon- 

 taneously inflammable body, which diffused an abomin- 

 able odour through the laboratory, was that terrible com- 

 pound which might have been formed by arsenic present 

 as an impurity in the zinc used in the reaction, and that 

 I might be already irrecoverably poisoned. These fore- 

 bodings were, however, quelled in a i^"^ minutes by an 

 examination of the black stain left upon porcelain by the 

 flame ; nevertheless, I did afterwards experience some 

 symptoms of zinc poisoning." 



The discovery of the large group of organo-metallic 

 bodies and the secondary investigations to which the 

 author was thereby led induced him to propound the 

 theory of " atomicity," now taught in one form or another 

 in our schools of chemistry. 



Having discovered the organo-metallic bodies just 

 referred to, Dr. Frankland appears to have turned his 

 attention to the production of analogous compounds con- 

 taining unmetallic bodies united directly with alcohol 

 radicles, and in this direction he was successful, as he 

 showed that boron could be made to afford some highly 

 interesting compounds of the desired kind. This line of 

 investigation, however, was not pursued to any consider- 

 able extent, as the author evidently desired to concentrate 

 his attention upon the study of the action of members of 

 the organo-metallic group upon various organic bodies, 



