354 



NATURE 



[August ii, 1898 



The locust disease fungus cultivated by Dr. Edington, 

 director of the Bacteriological Institute, Grahamstown, for the 

 purpose of destroying locusts, appears to be giving satisfactory 

 results. A writer in the Cape Agricultural Journal states that 

 he gave a number of healthy locusts ( Voelgangers) internal doses 

 of liquid in which cultures of the fungus had been dissolved, 

 and afterwards placed them among the locusts at the head of 

 three large swarms. On the fourth day after, numbers of locusts 

 died, and on the seventh day after the introduction of those 

 infected, the three swarms were entirely destroyed. 



Bacterial cultures have been made on almost all vegetables, 

 but the potato and the carrot are the principal ones which are 

 in daily use in bacteriology. M. Roger has, however, says the 

 Lancet, reported to the Paris Society of Biology that in his 

 opinion the artichoke possesses several advantageous qualities in 

 this respect. Nothing is more simple than to prepare it for the 

 purpose. After having stripped off the scales the thick part is 

 cut up into little cubes, care being taken to preserve the fibres 

 {fotn). The pieces are placed in tubes plugged with damp 

 wadding, the fibres being uppermost, so that the culture medium 

 is represented by a fleshy mass surmounted by a sort of tuft. 

 When the wadding is inserted the whole is heated in an oven to 

 II5°C. for a quarter of an hour. In making the inoculation 

 the germs must be deposited at the point of insertion of the 

 flowers. Speaking at the same meeting of the Society of 

 Biology, M. Carnot mentioned that he had ascertained that if a 

 small quantity of liquid derived from a previous culture of 

 Koch's bacillus is added to the ordinary culture media before 

 they are inoculated with tuberculous material the effect is to 

 hasten the growth considerably. In practice the same result is 

 obtained by adding some drops of tuberculin to the culture 

 media. If, on the contrary, the quantity of tuberculin is 

 increased — if, for instance, thirty drops are added to a culture 

 instead of five or six — the culture either does not undergo 

 development or else its development soon stops. 



A REMARKABLE testimony to the effectiveness of Prof. Haff- 

 kine's system of inoculation as a plague preventive is published 

 in a report on the inoculations among the Khoja com- 

 munity of Bombay, referred to in the Pioneer Mail. His 

 Highness Aga Khan, the head of the community, was himself 

 inoculated as an example to his followers, and he established an 

 inoculation station at Mazgaon, at which 5000 Khojas were 

 inoculated between December 1897 and April 20, 1898, 184 

 other Khojas being inoculated in municipal stations. The 

 daily strength of the inoculated for the period was 3184. It 

 is calculated that there were 9516 uninoculated persons in the 

 community, and among these there were 77 deaths from plague 

 and 94 from other causes during the period mentioned. Among 

 the 3184 persons inoculated during this period there were 

 three deaths from plague and four deaths from other causes. 

 These are the most striking results observed up to the present 

 time. Eliminating the five deaths from plague and the fifty-six 

 deaths from other causes which occurred among uninoculated 

 persons under the age of three or over sixty, the figures are still 

 sufficiently remarkable. There is a difference of 897 per cent, 

 of deaths from plague in favour of the inoculated part of the 

 community, and of 73-3 per cent, of deaths from other causes. 

 Prof. Haffkine is justified in saying that, making allowance for 

 inaccurate classification, and admitting that some of the deaths 

 among the uninoculated may have been those of sickly persons 

 who feared to undergo the operation, the results indicate that, 

 besides being a protection against plague, this inoculation 

 influences favourably the resistance to certain other diseases, a 

 fact with regard to which exact material is being accumulated at 

 the Research Laboratory at Bombay. 

 NO. 1502, VOL. 58] 



Proks. Lummer and Pri.ngsheim have communicated 

 to Wiedemann's Annalen the results of their determinations 

 of the ratio of the specific heats of certain gases. These results 

 were obtained from the relationship between temperature and 

 pressure in an adiabatic expansion of the gas, a new form of 

 bolometer being employed in the measurement of temperature. 

 The final values obtained for the ratio in question are : for air, 

 I "4025; for oxygen, 1*3977; for carbonic acid, 1*2995; *nd 

 for hydrogen, i"4o84. These values are rather greater than 

 those obtained by the same writers in 1887, when a silver wire 

 0*04 mm. thick was used in the bolometer. 



The problem of the flow of water in uniform pipes and 

 channels, said by Saint Venant to constitute a hopeless 

 enigma, forms the subject of a comprehensive paper by Mr. 

 G. H. Knibbs in the Journal and Proceedings of the Royal 

 Society of New South Wales (xxxi. ), The formulae used by 

 engineers in general are shown by the author to be syst- 

 ematically defective, even in respect of their mathematical 

 form, and the main object of the paper is to indicate a scheme 

 of empirical analysis of, and to develop a type of formula for, 

 the flow of water in pipes and channels. By means of tables, 

 the general expression supplied can be rendered easy of 

 manipulation for the purposes of practical calculation. Mr. 

 Knibbs concludes that the law of velocity as related to tem- 

 perature with at least two (or better, three) pipes of very different 

 roughness, requires further experimental investigation. The 

 variation of the velocity with respect to the radius of pipes also 

 needs investigation ; this evidently should be done with, at 

 least, three series having widely different degrees of rough- 

 ness, so as to ascertain the influence of the roughness upon 

 the variation. In channel investigations the author hopes 

 that the triangular form may be adhered to throughout ; the 

 law of flow may then be discovered, and the influence of 

 form constituted a subsequent subject of inquiry. 



An interesting series of determinations of the local variations 

 in the intensity of gravity in the vicinity of Mount Etna and in 

 Eastern Sicily generally is detailed by Signor A. Ricco in the 

 Atti dei Lincei, vii. (2) i. The observations were made with 

 the assistance of Colonel Von Sterneck's pendulums, kindly 

 lent for the purpose by the Hydrographic Bureau of Pola, while 

 the staff of the Observatory at Catania all took part in the work 

 of observing. The general results obtained are somewhat re- 

 markable. In the neighbourhood of Catania and Messina the 

 value of gravity, reduced to sea-level, exceeds that given by 

 theoretical formulae by about 150 x lO"* units, an amount 

 equivalent, according to Helmert, to that due to a stratum of 

 rock of density 2-5, of 1500 metres thickness. But this excess 

 diminishes rapidly in the neighbourhood of Mount Etna, and 

 becomes a minimum at the summit, where it is less than 

 50 X 10"^ units. This diminution appears somewhat difficult 

 to explain, even on the hypothesis of the existence of large sub- 

 terranean cavities within and beneath the mountain. Another 

 remarkable result is that at Catania the deviation of the vertical 

 is small, and in a direction away from Mount Etna ; this result, 

 however, obtains a satisfactory explanation, according to Signor 

 Ricco, in the attraction of massive basaltic rocks of Monte 

 Lauro to the south of the station. 



An elaborate memoir by Dr. J. Zenneck on the markings of 

 pythons, boas, and allied genera of snakes appears in the 

 current number of the Zeitschrift fiir wissenschaftliche Zoologie. 

 It consists of 384 pages and eight plates, and deals especially 

 with the nature and extent of the variation in colour-markings 

 possible within the limits of a species. Considering the great 

 number of specimens of each species which Dr. Zenneck has 

 had the opportunity of examining, the work should prove a 

 valuable addition to the literature of systematic herpetolcgy. 



