112 



NA TURE 



[May 31, 1S94 



last, appears in the May number of the Association's Pro- 

 ceedings, together with the presidential address on " Geology in 

 the Field and in the Study," delivered by Mr. H. B. Woodward. 



The late Prof. Milnes Marshall's little book on " The 

 Frog," kno*n to be a most concise introduction to anatomy, 

 histology, and embryology, has reached a fifth edition. A ' 

 note by Dr. Hurst informs us that the preparation of this 

 edition for the printer was Prof. Marshall's last professional 

 act, and was completed only a week before his death. 



The Marlborough College Natural History Society, founded 

 just thirty years ago, has issued its report for 1893. The report 

 chronicles the work of the sections of astronomy, botany, en- 

 tomology, geology, microscopy, zoology, and meteorology during 

 the year. It also includes an anthropometrical report contain- j 

 ing the statistics of weights and measurements,of members of the 

 school. This is a feature that other societies in our schools and 

 colleges would do well to take up, for the anthropological in- 

 formation thus collected is very useful. 



It is well known that many amateur photographers send their 

 negatives to professionals to be printed. The Indian amateur, 

 however, has usually to make his own prints, as there are few 

 professional photographers in the far East who undertake the 

 work. To make up for this dearth of available assistance, the 

 Journal of the F/wlografhic Society of India reports that the 

 society of which it is the official organ have established a print- 

 ing department for its members. Though such a departure 

 might be adversely criticised in the case of a British society, it 

 may be pardonable in India. 



Volumes viii. and ix. of the Annalen der k. k. Univer- I 

 sitixts-Sternwarte in Wien, edited by Prof. E. Weiss, have ' 

 recently been issued. The former volume contains the results 

 of meridian observations made at Vienna Observatory during 

 1886 and 1S87, of comet observations made between 1890 and ! 

 1892, and of observations for positions of planets, comets, and I 

 comparison stars. In vol. ix. are given the zone observations 

 made by Dr. Palisa during 1884 in connection with the Vienna 

 star catalogue. This volume also includes the results of obser- 

 vations of planets during 1890, and meteorological observations 

 made in 1887 and 1 888. 



Messrs. J. an-d A. Churchill have published a new 

 edition of " Materia Medica, Pharmacology, and Therapeutics," 

 by Dr. C. D. F. Phillips. The work originally appeared in 1882, 

 but was out of print for some years. Dr. Phillips has made 

 numerous emendations and additions in order to bring his book 

 in touch with the present state of knowledge of the physio- 

 logical and therapeutical actions of remedies. More than usual 

 space has also been devoted to pharmacy. The present volume 

 deals with the actions of inorganic substances, and a new edition 

 of its companion volume on the vegetable, animal, and organic 

 compounds will be published to supplement it. | 



The tidal streams round the Isle of Wight can be found at | 

 any hour on any day by means of an arrangement devised by 

 Mr. F. Howard Collins, and published by Mr. J. D. Potter. 

 A plan of the island, with arrows showing the directions of tidal 

 currents, is drawn in each of twelve sections of a cardboard 

 circle pivoted at the centre. This circle is capable of being 

 moved round inside another, upon which the hours from one to { 

 twelve are marked. When the inner circle has been set to the 

 time on the outer one at which high water occurs at Portsmouth, 

 the directions of the arrows opposite any hour on the latter 

 show the direction of the tide at that hour. Yachtsmen in the 

 Solent and round the Isle of Wight should find the chart \ 

 useful. I 



NO. 1283. VOL. 50] 



In the June number of Natural Science Dr. .\. R. Walla 

 compares the Palxarctic and Nearctic regions, as regards 

 families and genera of their mammalia and birds. It has becD 

 suggested by several zoologists that these two regions should be 

 united so as to form one new region — the Holarctic — co- 

 extensive with the extra-tropical northern hemisphere. Dr. , 

 Wall-ice finds, however, that the two regions, instead of being , 

 so much alike that they should be united to form a single region, | 

 are really exceptionally distinct, and that their union would not 

 be an improvement upon Dr. Sclater's system of zoological \ 

 regions. Thejournal also contains articles on the distinguishing of , 

 sex in ammonites, by Messrs. S. S. Buckman and F. \. Bather ; ^ 

 problems in experimental psychology, by Prof. E. B. Titchener; 

 the mode of formation of ground ice, by Mr. R. D. Oldham ; 

 the significance of the bird's foot, by Mr. F. Finn ; and cell- 

 division, by Mr. M. D. Hill. 



The new series of Science Gosiip is really an improvement 

 upon the old one. Each month pages are specially devoted 10 

 astronomy, notes and queries, science abroad, zoology, geology, , 

 botany, and transactions of scientific societies. The articles in ' 

 the June number include one by Mr. A. T. Tail, on the beauti- 1 

 ful dendritic crystals sometimes found on the pages of books. 1 

 The author remarks that he has never seen a specimen of these I 

 arborescent crystals in a book older than 1835 or younger than j 

 18S2, and that rather more than twenty years are usually re- | 

 quired for their fullest development. He has examined a large | 

 number of volumes of foreign origin, but has never discovered 

 any of the crystals upon their pages. The crystals are supposed 

 to owe their formation to chemical action set up by the acci- 

 dental deposition of minute fragments of copper upon the sur- 

 faces of paper during the processes of manufacture or printing, so 

 it is suggested that dilferences between British methods of 

 paper-making and printing, and those in vogue in America and 

 on the continent, may account for the absence of the crystals. 



I.\ a communication to the Soci^t^ Chimique, M. Girard 

 explains the interesting fact that when wood charcoal is heated 

 with sulphuric acid, for the purpose of preparing sulphur 

 dioxide, colourless crystals are frequently observed to form. 

 M. Terrell has previously pointed out the occurrence, but with- 

 out offering any evidence as to its nature. M. Girard now 

 finds that if excess of carbon is used, and the operation is con- 

 tinued until the complete cessation of the evolution of gas, so 

 large a sublimate of the crystals is obtained as to cover the sides 

 and neck of the flask, and to almost obstruct the delivery tube. 

 In order to purify the substance it is only necessary to dissolve 

 it in water, boil until sulphur dioxide is expelled, precipitate 

 any sulphuric acid by the necessary quantity of barium chloride, 

 evaporate to dryness, and recrystallise from alcohol. The well- 

 formed colourless crystals obtained are found to consist of 

 pyromellitic acid, CcH.jtCOOH),, one of the isomeric tetra- 

 basic acids of the benzene series, and the acid whose anhydride 

 is produced when mellitic acid is heated. Mellitic acid is a 

 substance well known from the fact of its occurrence in com- 

 bination with alumina in honey-stone. The crys;als of pyro- 

 mellitic acid obtained in the interesting manner above indi- 

 cated are soluble without decomposition both in boiling 

 sulphuric and boiling nitric acids. Their aijueous solution 

 reacts like an ordinary dilute acid, decomposing carbonates 

 with effervescence. The crystals themselves are efflorescent in 

 the air, and upon heating they volatilise with production of a 

 sublimate of long needles, melting about 280', and which prove 

 to be pyromellitic .anhydride. M. Girard further shows that 

 when sulphuric acid reacts upon wood charcoal which has pre- 

 viously been well calcined at a white heal, or upon coke, no 

 production of pyromellitic acid is observed. On the other 

 hand, substances richer in hydrogen and oxygen than wood 



