May 1 1, 1893] 



NATURE 



39 



A NEW reaction, of wide general application and of consider- 

 able practical utility, by means of which the important organic 

 compounds known as nitriles may be readily prepared in a 

 state of purity, has been discovered by Prof. Michaelis and Dr. 

 Siebert, and is described by them in the current number of 

 Liebig's Aniialen. As stated in our chemical note of last week, 

 Prof. Michaelis has recently been studying the action of thion)l 

 chloride, SObl,, upon the primary amines, and has shown that 

 the product of the reaction is a thionylamine, a compound 

 formed by the replacement of the two hydrogen atoms of the 

 NHo group of the amine by the radical thionyl, SO. In seek- 

 ing to ascertain whether a similar kind of compound to the 

 thionylamines is formed when thionyl chloride is allowed to act 

 upon the amides of the acid radicles, Pjof. Michaelis and Dr. 

 Siebert have discovered the new mode of preparing the nitriles. 

 Instead of a compound of such a nature being produced, a 

 nitrile is the main product, with sulphur dioxide and hydro- 

 chloric acid as bye products. As the two latter are gaseous 

 substances, it is at once evident that the reaction must aff )rd 

 a particularly convenient mode of preparing the nitriles in a 

 state of purity. The reaction, moreover, is quite general, and 

 is applicable both in the fatty and in the aromatic series. 

 When thionyl chloride is brought in contact with acetamide, 

 CH3 . CO . NH2, a violent reaction occurs, with considerable 

 rise of temperature. After a few minutes, however, the violence 

 diminishes, and the liquid eventually becomes quiescent. In 

 order to complete the interaction, the product should then be 

 heated over a water-bath for a few hours, the reaction flask 

 being provided with a reflux condenser. When the fumes of 

 hydrochloric acid and the odour of sulphur dioxide are no 

 longer perceptible, the reaction is completed in accordance 

 with the equation — 



CH3 . CO . NHj + SOblj = CH3 . CN -f- SO2 + zHbl. 

 The dark-coloured liquid is then decanted from a small quan- 

 tity of resinous products of decomposition and distilled, when 

 pure acetonitrile, clear and colourless, passes over it at its 

 boiling point, 82°. The yield of pure nitrile is about half the 

 weight of acetamide employed. The violence of the reaction 

 between thionyl chloride and acetamide is very much diminished 

 by the addition of benzene ; but owing to the difficulty of 

 separating the resulting nitrile from the benzene by fractional 

 distillation, it is preferable not to employ it. With care, the 

 direct addition of the thionyl chloride may be made without 

 loss. Propionamide reacts in a very similar manner with 

 thionyl chloride, and almost the whole of the liquid product 

 distils over quite colourless at the boiling point of propioni- 

 trile (98'). In like manner, pure benzonitrile may be obtained 

 by the action of thionyl chloride upon the amide of benzoic 

 acid. Il is preferable, however, in case of such higher boiling 

 nitriles which can be readily separated from benzene by frac- 

 tional distillation, to conduct the operation in presence of 

 benzene, the reaction then proceeding much more regularly and 

 without the violence of the diiect action. Upon subsequent 

 distillation, the thermometer at once rises to 190' after the dis- 

 tillation of the benzene, and remains constant at that tempera- 

 ture until almost the whole of the benzonitrile has passed over. 



Notes from the Marine Biological Station, Plymouth. — 

 Last week's captures include the Hydroid Hydractinia echinala, 

 the Polychaeta Eunice Harassii and Siphonostoma uncinalum, 

 the Polyzoan Prdicellina certiua, the Opisthobranchs Ktincina 

 coronata and Polycera Lessonii, the Crustacean Hyas araneus, 

 and the Echinoderms Cucumaria Planci and Luidia ciliaris. 

 The quantity of gelatinous algje in the Channel waters at length 

 exhibits signs of diminution. Medu.sa; of the remarkable 

 Hydroid Corymorpha nutans (of Allman) have been taken in 

 the tow-nets on several occasions. The medusae of Aurelia 



NO. 1228, VOL. 48] 



aurita are growing rapidly in size, and have now attained an 

 avefage diameter of l\ inches. The Megalopa of Carciuus are 

 no longer commonly taken in the tow-nets, but are chiefly to be 

 found in especial haunts at the sea-bottom. The following 

 animals, not hitherto noted, are now breeding : the Hydroids 

 Plumiilaria setacea and Antennularia ramosa, the Decapod 

 Crustacea Crangon fasciatus and Hippolyte Cranchii, the 

 Ophiurid Amphiura ehgans (= squamata), the Ascidian Slye- 

 lopsis grossularia, and several species of Amphipoda and 

 Pantopoda. 



The additions to the Zoological Society's Gardens during the 

 past week include two Mozambique Monkeys [Cercopithecus 

 pygerythrits, 9 9 ) from East Africa, presented respectively by 

 Mr. Arthur James and Miss Maude Parkinson ; a Rhesus 

 Monkey {Macacus rhesus, 9 ) from India, presented by Miss G. 

 Lloyd ; a Bonnet Monkey (Macacus sinicus, 9 ) from India, 

 presented by Mr. R. Hughes ; a Macaque Monkey (Macacus 

 cynomolgus, 9 ) from India, presented by Mr. F. Byfield ; an 

 Indian Buffalo (Bulialus bujjelus, 9 ) from India, presented by 

 H.H. The Maharaja of Bhoonagar ; a Common Hedgehog 

 {Erinaceus europaus) British, presented by Mrs. E. Austen- 

 Leigh ; a West African Love- Bird (Agapornis pullaria) itom 

 West Africa, presented by Lady Theodora Guest ; two Herring 

 Gulls {Larus argentatus) British, presented by Mr. W. H. 

 Aplin ; two Egyptian Mastigures (Uromastix spinipes) from 

 Egypt, presented by Mr. Edmund Lamb ; a Moorish Tortoise 

 ( Testudo mauritanica) from North Africa, presented by Mi. T. 

 W. Bayley ; seven Green Tree Frogs (ffyla arborea) South 

 European, presented by the Rev. C. D. Fothergill ; a Silvery 

 Gibbon {Hylobates leuciscus) from Malacca, a Roseate Cockatoo 

 (Cacatua roseicapilla) from Australia, twenty Green Tree Frogs 

 {Hyla arborea) South European, deposited ; two Amherst 

 Pheasants (IhaumaUa amherstia, 9 9 ) from Szechuen, China, 

 a Swinhoe's Pheasant (Euplocamus svinhoii, i ] from Formosa, 

 three Cat Fish (Amiurus catus) from North America, purchased ; 

 a Common Crowned Pigeon ( Goura coronata) from New Guinea, 

 received in exchange ; a Yak (Poephagus grunniens), $ ), a 

 Water Buck (Cobus ellipsiprymnus, x ), an Angora Goat [Capra 

 hhcus. var. i ,), a Bennett's Wallaby (Halmaturus bennetti, i ) 

 born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



Meridian Circle Observations. — At the meeting of the 

 Royal .Astronomical Society, held on April 14 last, the proceed- 

 ings of which are recorded in the current number (No. 201) of 

 the Obsen'atory, the paper prepared by Messrs. Turner and 

 HoUis (and read by 1 he former) entitled, " Comparison of the 

 Greenwich Ten-year Catalogue (18S0) with the Cape Catalogue 

 (1S80),'" was the means of instigating an interesting discussion 

 with reference to questions relating to systematic error of 

 meridian observations. The questions thus raised are of great 

 importance, for, as Dr. Gill remarks, they " afftcl the objects for 

 which public oli.<^ervatories were founded." Generally speaking 

 the comparison of the catalogues above mentioned seems to have 

 given very satisfactory results, but the series of differences ob- 

 tained from the norlh-polardistjinces, arranged in order of north 

 polar distance, showed signs of small divergences. The source 

 from which these differences could have arisen seems — since the 

 accuracy of the N.P. D. places depends on the coefficient of 

 refraction — to be at first sight apparent, and Mr. Stone's opinion 

 is that this quantity is " practically mixed up with the question 

 of refraction," his firm conviction being that in the Cape obser- 

 vations there are no systematic errors possible to account for 

 o"4. Dr. Gill, in referring to the discussion generally, made 

 some very striking remarks about meridian observations, and 

 was of opinion that at the Cape there were sources of syste- 

 matic error amounting possibly to half a second of arc. The 

 differences obtained from the refltx and direct observations at 

 the Cape, he says, have led him to the conclusion that they are 

 caused by the fact that, " since the walls of the transit room are 



