June 15, 1893] 



NA TURE 



157 



(6) the fillet test applied to the veinsof the arm caused no filling 

 of veins on the distal side of the fillet ; (7) the subcutaneous 

 injection of ammonia caused the dirty brown stain indicative of 

 dissolution ; (8) rigor mortis was detected on making careful 

 movements of the joints of the extremities and of the lower jaw. 

 Two tests, however, indicated that life was not extinct. The 

 opening of a vein to ascertain whether the blood had undergone 

 coagulation showed that the blood was fluid. This is not very 

 important, because under abnormal conditions the blood may 

 remain fluid after death has occurred. But a criterion which 

 has been believed to afford sure evidence of life or death was 

 found to fail. It is known as the diaphanous test, and consists 

 in holding the fingers of the supposed dead person in front of a 

 strong light, and looking through the narrow spaces between 

 two fingers just touching one another. The belief has been that 

 if the person is alive a line of scarlet colour will be seen, and 

 that the absence of the colour indicates death. In the case in- 

 vestigated, however, the scirlet line of light between the fingers 

 was clearly visible, though death was assured by the fact that 

 decomposition set in. Further, Sir B. W. Richardson records 

 a case in which the test, applied to the hand of a lady who had 

 simply fainted, gave no evidence of the scarlet line; so that, on 

 that test alone, she would have been declared dead. Thus the 

 diaphanous test, which has been considered by many as infallible, 

 has been proved to be untrustworthy. 



Herrn Friedlander und Sohn, of Berlin, have issued 

 their Natural History News, Nos. 3-9. The lists contain 

 advertisements of recent literature on natural history. 



The Technical Instruction Committee of the Essex County 

 Council have just issued a prospectus containing syllabuses of 

 lectures on chemistry and biology — sciences which are specially 

 applicable to the industries of the county. 



Iron has ceased to exist as an independent journal, after living 

 for twenty years under that title and fifty years as the Mechanics'. 

 Magazine. It has been amalgamated with Industries, and the 

 combined journal will in future be issued under the title of 

 Industries and Iron. 



The life of Sir Richard Francis Burton, by Lady Burton, 

 will shortly be published by Messrs. Chapman and Hall. The 

 work will recount Sir Richard's life from his birth to his death, 

 and will comprise two volumes of about 600 pages each. A large 

 amount of space is devoted to a description of his explorations. 



We have received the New South Wales Statistical Regisler 

 fur 1891 and previous years, compiled from official returns by 

 Mr. T. A. Coghlan. The volume is a collection of eight parts 

 which have already been issued separately. It is wholly de- 

 voted to statistics. 



Fro.m Felix Alcan, of Paris, comes a work on the "Con- 

 qiiete du Monde Vegetal," by Louis Bourdeau. The arrange- 

 ment of the matter in the book is very good. After discussing 

 the general theory of the growth of plants, the author passes to 

 the study of various groups of plants of economic and of orna- 

 mental value. This branch of the subject is divided into seven 

 parts. The operations of culture furnish matter for a special 

 chapter, and the book is concluded with an account of the 

 creation and preservation of artificial varieties of some types of 

 plants. To a large extent the subject is treated historically. 



The Life Saving Society has for its chief object the development 

 of instruction in such swimming arts as would be of assistance 

 to a person endeavouring to save life. They have just issued a 

 revised edition of an excellent little handbook in which an 

 account is given of the methods recommended by the society 

 for the rescue of the drowning and the resuscitation of the 

 apparently drowned. It is hoped that the issue of this course 

 of instruction will lead to the subject of life-saving and resusci- 

 tation being included in the curriculum of every school. 

 NO. 1233, VOL. 48] 



The decomposition of steam by means of heated magnesium 

 makes, according to Herr Rosenfeld {Berichte), a pretty lecture 

 experiment. A short piece of a combustion tube is furnished at 

 one end with a stopper and tube for escape of gas, and con- 

 nected at the other with a vessel containing water. A little 

 powdered magnesium (o'5 to i gramme) is put in the tube, and 

 cautiously heated ; then, by gently heating the water, steam 

 passes over, and the metal merely glows. In this way is ob- 

 tained a steady current of hydrogen, which can be collected 

 over water. But if a rapid current of steam is sent over 

 the heated metal, the latter burns with dazzling light, and the 

 heat breaks the tube. This occurs, however, only after some 

 time, when a good deal of hydrogen has been collected in the 

 bell-jar. 



An interesting compound of aluminium chloride with 

 benzoyl chloride, the chloride of the benzoic acid radicle, has 

 been obtained in large crystals by M. Perrier, and an account of 

 it is contributed to the current number of the Comptes Rendus. 

 Such compounds are of particular importance in view of the 

 remarkable role which aluminium chloride has been found to 

 play in synthetical chemistry, as affording some insight into the 

 nature of the intermediate reactions upon which the apparently 

 catalytic action of this useful salt depends. The new compound 

 now described is represented by the formula CgHjCOCl. AlClj, 

 or, if aluminium chloride is considered as represented by the 

 usual double formula, (CgHjCOCIjj.AljClj. It is readily pre- 

 pared by heating about ten grams of benzoyl chloride dissolved 

 in 150 c.c. of carbon bisulphide with nine grams of anhydrous 

 aluminium chloride in a flask fitted with a reflux condenser. 

 After three hours' ebullition and subsequent cooling a large 

 yield of the colourless tabular crystals of the new compound is 

 obtained. The crystals decompose somewhat rapidly in moist 

 air, and they are instantly decomposed by water, forming an 

 aqueous solution of aluminium chloride, hydrochloric acid, and 

 benzoic acid. They are readily soluble, however, without 

 decomposition, in carbon bisulphide. The formation of com- 

 pounds of this nature is not confined to the chloride of benzoic 

 acid, but would appear to be general throughout the aromatic 

 series, and M. Perrier has already isolated in a pure state the 

 corresponding compound containing the chloride of phthalic 

 acid. Moreover, in the fatty series the chloride of butyric acid 

 is found to combine readily with aluminium chloride, in carbon 

 bisulphide solution, to form a compound of the same definite 

 nature. 



These compounds are not the first of the kind that have been 

 prepared. Last year MM. Perrier and Louise described a con- 

 siderable number containing the aromatic ketones, ethers, and 

 phenols. They were all constituted upon the same type, 

 Mj. AljClj, where M represents a molecule of a ketone, ether, 

 or phenol. The compound containing acetophenone, for instance, 

 (CgHj.CO.CHj^j. AljClg, may be obtained in good crystals by 

 cooling the liquid formed by heating acetophenone dissolved in 

 carbon bisulphide with aluminium chloride to 40°. Similarly 

 the compound with phenyl benzoate, (Culls. CGOCijHsJj.AljClj, 

 crystallines from the liquid obtained by heating the components 

 in caibon bisulphide solution. They are all of the same character, 

 permanent in carbon bisulphide solution or in dry air, but de- 

 composed rapidly by moisture. 



The formation of the above compounds explains at once the 

 important synthetical method introduced by MM. Friedel and 

 Crafts for the preparation of the aromatic ketones by the action 

 of the hydrocarbons upon the chlorides of the acid radicles in 

 presence of aluminium chloride. It is most probable that a 

 compound of aluminium chloride with the chloride of the acid 

 radicle, (R.CGCOj.AI^CIc, is first formed, and that this is sub- 

 sequently converted by the hydrocarbon into the compound of 



