554 



NATURE 



[October 4, 1900 



a substance which in character bears a very striking resemblance 

 to gutta-percha. As the material cools it becomes exceedingly 

 hard, but while soft it can be moulded into any required shape. 

 The fruit of the tree resembles a peach in shape, but grows to 

 the size of a small melon. Experts have experimented with 

 this new product to see if it in any way possesses the qualities 

 of gutta-percha, and although it is not expected to prove 

 equal to the genuine article, it is considered that it will be 

 quite suitable for some purposes for which gutta-percha is at 

 present utilised, and it will thus become a marketable article. 

 It is said to abound in Zanzibar, and will be a very cheap 

 product. 



Writing to thQ British Medical Journal on the subject of 

 *' Mosquitoes and Malaria," Mr. H. J. Elwes, F.R.S., says :— 

 "The connection between mosquitoes and malaria seems to be 

 now so clearly proved that some experiments should be under- 

 taken by the Indian Medical Department to find out under what 

 conditions mosquitoes do not produce malaria. Some years ago 

 when on a hunting expedition in a very malarious district in the 

 Bhotan Terai, I succeeded in escaping malaria by keeping within 

 mosquito curtains till after sunrise, and getting into them again 

 as soon as possible after dark, smoking freely at the same time 

 within the curtains of my camp bed. Two out of the four 

 Europeans of my party, and nearly all the natives who did not 

 take these precautions, suffered so severely from malaria that 

 our camp was unable to march after three weeks in the district. 

 I may mention that it was then observed by experienced officers 

 that from fourteen to eighteen days was the time which elapsed 

 between exposure to infection and the appearance of severe 

 fever. But there are places in Eastern Bengal and no doubt 

 elsewhere where mosquitoes are very numerous and annoying, 

 which do not seem to be subject to severe malaria, and I re- 

 member that Dacca, the only place where I was kept from 

 sleeping a whole night by mosquitoes, was looked on as a station 

 free from severe malaria, and I certainly, though I had pre- 

 viously been suffering from fever in Assam, never had a touch of 

 it there. The great importance of finding out as soon as possible 

 what precautions should be enforced by those responsible for 

 the health of soldiers and others who are obliged to live in 

 malarious districts cannot be overrated." 



In his report on the work of the Government Laboratory, 

 Dr. T. E. Thorpe refers to the examination of some ordinary 

 writing ink which was submitted to him by the Stationery Office, 

 on a complaint that it thickened excessively and clogged the 

 pen, and, in illustration, a sample of the contents of the ink- 

 wells in use in the particular public office was forwarded, to- 

 gether with a sample of the ink as supplied. It was found that 

 after the deposition of the separated solid matter of the ink, col- 

 lected from the ink-wells in use, the fluid portion had a specific 

 gravity twice that of the ink supplied. In other words, the ink 

 had been allowed to become concentrated by evaporation to prac- 

 tically double its original strength through the use of excessively 

 large ink-wells and inattention to the supply. It is, of course, 

 necessary that the ink supplied shall be capable of furnishing a 

 record which may be relied upon as permanent. Ink made 

 with tannin and iron salts has had the advantage of very ex- 

 tended and prolonged use, with the result that complete confi- 

 dence is felt as to the permanence of writing, for which it is 

 used. But ink of this character possesses the undoubted dis- 

 advantage that it rapidly thickens on exposure, and Dr. Thorpe 

 points out that it is specially advisable that such ink should be 

 used in ink-wells of small size which receive regular attention at 

 short intervals. 



It may safely be said that as petrol stands to-day as the 

 paramount means of propulsion for automobiles accommodating 

 passengers and of a light character, so steam has forced its way 

 NO. 1614, VOL. 62] 



(at least in this country) as the means adopted for heavy motor 

 vehicles for road service, carrying a load varying from three to 

 ten tons. In support of tliis argument, an interesting article is 

 given in the Engineering Magazine for September, describing 

 these heavier types of vehicles, and although all typical designs 

 are mentioned in every case, not petrol, but steam, represents 

 the power used. As can be well imagined, these heavier class 

 of waggon have had many difficulties to overcome, and with the 

 exception of one type, a ten ton steam motor waggon by Messrs. 

 C. and A. Musker, of Liverpool, the general designs are 

 practically the same. The Thorneycroft waggon is fully 

 described and illustrated in its diflferent applications, ranging 

 from the tipping dust van to a steam delivery waggon, and pro- 

 vided with a "trailer," by which is meant a vehicle towed 

 behind. The ratios of gearing between the engine and the 

 driving axle are lo'i and 177 to i. On all ordinary gradients 

 five or six tons can be taken, two of which are conveyed on the 

 trailer. Several other waggons by different makers are illus- 

 trated, with their dimensions graphically stated. The chief 

 differences lie in the position and type of the engine, the power 

 transmitted to the driving wheels in different ways, various 

 kinds of boilers and different working pressures employed, and 

 slight external appearance. The " Musker," already referred 

 to, is only in its experimental stage, its chief features being an 

 efficient liquid fuel burner combined with a flash-type boiler 

 built up of three cylindrical coils of strong steel tubes, and the 

 flame circulating in the annular space between them. All 

 machinery is placed beneath the " body," thus affording a 

 larger loading area than any other vehicle. It remains to be 

 seen, however, whether the advantage claimed will be realised ; 

 if so, and considering its great load capacity (ten tons), it is 

 indeed an important step in this branch of engineering. 



A REPORT on the geology of the West Moreton or Ipswich 

 coal-field in Queensland, by Mr. W. E. Cameron, has been 

 published at the Geological Survey Office, Brisbane. It is 

 accompanied by an appendix on the economic value of Queens- 

 land coal by Mr. Robert Wilson. The Ipswich coal-field is 

 estimated to cover an area of about 12,000 square miles, and 

 the coal has been most extensively worked in the neighbourhood 

 of the town of Ipswich, which is about twenty-five miles south- 

 west of Brisbane. The strata are of Jura-Trias age, and they 

 are a good deal folded and faulted. They yield workable 

 coals from two to four feet and more in thickness. Experiments 

 made on the Government steamer Oder by Mr. Wilson show 

 that some varieties are very good and useful steaming coals ; 

 and that generally the coals of Queensland ' ' are well able to 

 hold their own with any others at present found in Australia." 

 The report is illustrated by a detailed geological map en a scale 

 of an inch to twenty chains, and also by a geological map of a 

 large area on the scale of an inch to a mile. 



The third volume of the Annales of the French Meteoro- 

 logical Office, containing rainfall values and completing the 

 observations for the year 1897 (see p. 490), has been published 

 in a greatly reduced form. The daily rainfall values are given 

 for three hundred stations only, instead of nine hundred, and 

 the scale of the rainfall charts has also been reduced. The 

 valuable series of monthly and annual summaries are given for 

 all stations, as before. 



In the Botanical Gazette for August, Prof. D. G. Fairchild is 

 enthusiastic as to the advantages presented by the Botanic 

 Garden at Rio de Janeiro for the study of tropical botany, 

 although at present no facilities are afforded for teaching or 

 study. lie regards Rio, with its fashionable suburb Petropolis, 

 as the most picturesque city in South America. To any botanist 

 who wishes to study tropical vegetation, Petropolis and the 

 other suburbs of Rio will prove the most attractive place in the 



