374 



NATURE 



[August 20, 1903 



sanitary milk supply are the most important. Dr. Fremlin 

 describes the cultivation of the nitroso-bacterium, and Dr. 

 Durham a new diluting pipette. Dr. Haldane finds that 

 the presence of sulphur in coal-gas is the principal factor 

 in vitiating the air, and Dr. Savage has investigated the 

 relation between the pathogenicity of bacillus coli in drink- 

 ing water and purity. Dr. Graham-Smith describes further 

 researches upon factors which may modify the biological 

 or precipitin test for blood. 



Dr. Roberto Borola, of Pavia, contributes to the 



Lombardy Rendiconti, xxxvi. 12, a note on the metric 



properties of quadric surfaces in non-Euclidean geometry, 



dealing with circular sections, foci, and confocal and con- 

 cyclic systems of quadrics. 



An interesting extension of the use of Green's functions 

 to the mathematical theory of conduction of heat is given 

 by Prof. H. S. Carslaw, of Sydney, in the Proceedings of 

 the Edinburgh Mathematical Society, xxi. The use of 

 Green's functions has hitherto been mainly confined to the 

 theory of the potential, although their use in connection 

 with heat conduction has been mentioned by Minnigerode 

 and Betti. Prof. Carslaw now shows how the functions in 

 question can be obtained by means of contour integrals, and 

 a general method applied to the solution of problems which 

 are usually solved by independent methods. 



" Red rain " forms the subject of a paper by Messrs. F. 

 Chapman and H. J. Grayson in the Victorian Naturalist 

 for June. The occurrence of dust-laden showers is not in- 

 frequent in Australia, but one of the most remarkable 

 showers of this kind occurred on February 14 of this year. 

 The writers describe analyses of samples of sediment 

 collected from this shower at Camberwell and St. Kilda, 

 and they compare the substances observed with the minerals 

 contained in the dust commonly present on the roof of the 

 National Museum, Melbourne. A sample collected in a 

 second shower of " red rain " at St. Kilda on March 28 

 was also examined. The latter sediment was remarkable 

 for the number of diatoms it contained, and the authors 

 enumerate a list of the forms found, including about twenty- 

 five species. 



The coefficient of thermal surface-conductivity across the 

 surface of separation of a solid and a fluid is a quantity 

 the determination of which is of considerable importance, 

 especially in connection with the construction of boilers. 

 In the Zeitschrift of the German Engineers' Association, 

 Mr. L. Austin describes experiments made at Charlotten- 

 burg on this subject, giving the following results : — From 

 metal to water at the boiling point the resistance is equiva- 

 lent to a thickness of 1-2 to 2cm. of iron, but is reduced 

 by stirring by an amount equivalent to about o-75cm. of 

 iron. The resistance increases as the temperature falls, 

 reaching a maximum of locm. of iron, which is reduced 

 by icm. by stirring. For flow of heat from water to metal, 

 the resistance appears greater than for the reverse flow if 

 th^ water is undisturbed, and about the same when tke 

 water is stirred. 



The Atti dei Lincei, xii. 10, contains a brief account of 

 experiments in syntonic wireless telegraphy carried out at 

 Spezia under the direction of th-^ Minister of Marine. At 

 '-an Vito two Marconi apparatus of frequencies " A " and 



B" were connected with the same antenna, and com- 

 munication was carried on simultaneously with Palmaria 

 and Leghorn at distances of respectively 5 and 70 kilo- 

 metres. 



NO. 1764, VOL. 68] 



In the Atti dei Lincei, xii. 11, Prof.. G. Agamennone 

 directs attention to an interesting contribution to our 

 knowledge of terrestrial magnetism in the form of a dis- 

 course by Father Francesco Eschinardi, published in 1681, 

 in which he makes mention of a sudden change in the 

 magnetic declination at Rome from about 3° to 5° W., 

 which occurred towards the end of October of the previous 

 year. This the writer attributed to the effect of earth- 

 quakes in Spain and Malaga. 



The annual list of new garden plants ■of the year 1902, 

 which is issued as an appendix to the Kew Bulletin, has 

 been received. 



A record of plants collected in the northern region of 

 Yucatan is commenced in the Publications of the Field 

 Columbian Museum. The first fascicle, vwhich treats of 

 the ferns included in the Polypodiacese and Schizaeaceae, 

 and the monocotyledonous orders Gramineae and Cyperaceae,. 

 is the joint work of Mr. C. F. Millspaugh and Miss Chase. 



The question of shade for coffee and cocoa plants is dis- 

 cussed in the Jamaica Bulletin of the Department of Agri- 

 culture, where it is pointed out that in many cases it is 

 the bacteria working in the soil, and not the plants which, 

 require the shade. The choice of leguminous plants for the 

 purpose is a wise one, as the nitrogenous contents of the 

 soil are thereby increased. An article by Mr. Cousins,, 

 contrasting the constituents of four definite phosphatic 

 fertilisers, serves to point the absurdity of an indiscriminate 

 application of commercial fertilisers without taking into 

 consideration the nature of the soil. 



Whatever may be the outcome of the present political 

 question of fiscal reciprocity towards our colonies, there 

 can be no doubt about the advantages- of a closer connection 

 between them and the mother country. To further 

 this object a scientific and technical department of the 

 Imperial Institute was established, and a laboratory was 

 provided wherein samples of raw material from the 

 colonies can be analysed and reported upon by experts, 

 as has long been done for vegetable products at Kew. 

 It the second number of the Bulletin of the Imperial Insti- 

 tute, there appears an account of recent investigations 

 undertaken by Dr. Dunstan and his assistants. These 

 include the examination of rubbers from Africa, oil shale 

 from Natal, iron ore from a district in the Bombay presi- 

 dency, and other products. Also there are added special 

 notices on various industries which are receiving attention 

 in our dependencies and those of other European States. 



In vol. ii. of Marine Investigations in South Africa 

 Mr. R. Kirkpatrick, of the Natural History Museum, con- 

 tinues his descriptions of the sponges, naming some new 

 genera and species. 



The nature of the so-called terminal buds of fishes — 

 organs scattered over the skin of the head in certain 

 teleosts and ganoids, and at one time regarded as tactile 

 in function — forms the subject of an article by Mr. C. J. 

 Herrick, published in vol. xii. of the Journal of Comparative 

 Neurology. It is inferred that these structures have no 

 connection with the lateral line system, but are intimately 

 related to the taste-buds of the mouth. 



The July issue of the Emu contains a number of 

 interesting articles devoted wholly, or chiefly, to orni- 

 thology. In treating of New Zealand cormorants. Captain 

 F. W. Hutton suggests that one group of these birds 

 reached New Zealand from South America, and that, after 

 considerable modification in the Antipodes, their descend- 

 ants returned to their ancestral home, whence some found 



