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NA TURE 



[June 21, 190& 



As a result of visiting several of the more important 

 herbaria in Europe to study the genus Eupatorium and 

 several allied genera, Mr. B. L. Robinson has published 

 some notes on the Eupatoriea? in the Proceedings of the 

 American Academy of Arts and Sciences, vol. xlii.. No. i. 

 In addition to the diagnoses of new species of Eupatorium 

 and othi-r genera, the pamphlet contains revisions of the 

 genera Piqueria and Ophryosporus, also a discussion of 

 the genus Helogyne. 



.A SL'G.AR experiment station was instituted in Jamaica 

 in -April, 1904, under the direction of Mr. H. H. Cousins, 

 for investigating problems in connection with the sugar 

 and rum industries. The report for 1905 indicates what 

 is being done in the matter of cultivation experiments to 

 test different manures and varieties and to select new 

 seedling canes. The advantage to be gained by taking 

 new varieties into cultivation is well shown by the results 

 (obtained on the Albion Estate, where the Mt. Blanc 

 variety generally grown produces less than any other 

 variety tested, and furnishes less than half the saccharose 

 yield per acre of the seedling B379. 



.\n inquiry into the manufacture of Jamaica rums, by 

 Mr. C. .Allan, occurring in the above report, deals with 

 ferment.-ition changes, more especially those that give 

 the quality to flavoured rums. It appears that the flavour 

 is due mainly to the large amount and nature of the 

 ethers formed. Premising that the characteristics of 

 Jamaica rum are derived from saccharine liquors rich in 

 albuminous matter fermented by yeasts and bacteria, in 

 the case of the high-flavoured rums bacterial action is 

 greatly increased and special bacteria are developed, pro- 

 ducing acids that in combination with alcohol form 

 .aromatic ethers. It is suggested that higher alcohols, 

 furfurol, and aldehydes may help to give bodv to the 

 spirit. 



In a paper read before the National .Academy of .Sciences, 

 L.S.,A., on .April 17, the distinguished seismologist Major 

 C. E. Dutton discusses the possible relationhip between 

 volcanic action and radio-activity. The theory brought 

 forward is that, in limited tracts at depths of less than 

 four miles, rocks are melted by heat due to radio-activity. 

 -As the melting proceeds, the water contained in the rocks 

 becomes explosive and an eruption follows. When all the 

 lava is exhausted the reservoir is closed. In due course 

 more heat is generated, rocks are again melted, and a 

 second eruption takes place. This explains, not onlv the 

 repetitive character of eruptions, but the comparatively 

 shallow depth at which they originate. The horizon of 

 molten rock, if it is dependent on secular cooling of the 

 world, would be at a depth of 30 miles or 40 miles, while 

 if it is due to radio-activity it may possibly be found at a 

 depth of three or four miles. 



An interesting supplement on modern air compressors, 

 covering twenty pages with seventy-three illustrations^ 

 is published with the Engineer of June 15. It gives an 

 excellent review of the great strides made during the last 

 fifteen years in the use of compressed air. The develop- 

 ment of the use of compressed air as a means for trans- 

 mitting power appears the more remarkable when it is 

 remembered that during the same period the use of elec- 

 tricity for that purpose has grown enormously. 



The Engineering Standards Committee has made 

 arrangements with a firm at Bilston to manufacture com- 

 mercial sets of standard pipe-flange templates in large 

 quantities. The templates are made, with extreme 

 NO. IQI2, VOL 74] 



accuracy, of thin steel plate painted over with aluminium 

 paint, a small piece being cut out at the extremity of each 

 centre line so as to enable the fitter to see that the centre 

 line of the template coincides with the centre line of his 

 flange. The existence of these templates should enable 

 full advantage to be taken of the standardisation that the 

 committee has sought to effect. 



In a note to the Rendiconti della R. Accadcinia Jci Lincei 

 (dated April 22 last) Dr. F. Eredia gives the monthly and 

 yearly rainfall values obtained at the Collegio Romano for 

 eighty-one years, 1S25-1905. Observations were begun 

 there in 1788, but their continuity and uniformity were 

 not quite satisfactory prior to 1825. The annual mean for 

 this long period is 31-8 inches. The wettest months are 

 October to December ; the maximum fall in any month 

 was 14-7 inches, in November, 1878. 



The weather report issued by the Meteorological Office 

 for the week ending Saturday, June 16, shows that the 

 weather for the period was fine and dry generally. The 

 sky was cloudy in the eastern and southern counties of 

 England, and some rain fell in all districts. Thunder- 

 storms occurred in various parts of England on June 12 

 and 16. Temperature was generally low for the time of 

 year, and in the east of England the mean was 4° below 

 the average. At Dumfries, in the west of .Scotland, the 

 thermometer rose to 83°, and in the east of Scotland and 

 in the north-east of England it exceeded 80°. In the north 

 of Scotland the range of temperature for the week amounted 

 to 49°. The winds were mostly from between north and 

 north-east. 



.An illustrated price-list of echelon diffraction gratings, 

 just issued by Messrs. Adam Hilger, 75(1 Camden Road, 

 N.W., will be found to be of interest by all practical 

 spectroscopists. The gratings contain from ten to forty 

 plates, the corresponding prices, including suitable mounts, 

 ranging from 13/. to 120/. The heights of the plates vary 

 from 32 mm. to 40 mm., but can be made higher than 

 this if desired. The standard width of each step is i mm., 

 and the thickness of each plate about 10 mm., but this 

 latter dimension may be increased, with a corresponding 

 increase in price, if so desired. The list also contains 

 illustrated descriptions of the more generally used arrange- 

 ments of the echelon apparatus and of the auxiliary spectro- 

 scopes and various accessories employed. Messrs. Hilger 

 make a speciality of the constant deviation spectroscope 

 most usefully employed with echelon gratings, and have 

 just made an important alteration in the adaptation of the 

 telescope and collimator which will greatly increase their 

 rigidity, though the price remains the same. 



The results of a study of the infra-red region of the 

 spectrum, made by M. Milan Stefanik at the Meudon 

 Observatory, appear in the Comptes rendus for April 30. 

 While working with the solar eclipse expedition in Spain, 

 M. Stefanik found that, by placing a dark red screen 

 before the slit of his spectroscope, he was able to see to 

 a considerable distance into the infra-red. This led hifn 

 to continue a research on this matter on his return to 

 Meudon, where he employed a spectroscope having two 

 prisms, containing benzine and carbon bisulphide re- 

 spectively, and used as the light source an image of the 

 sun projected on to the slit by a lens, after reflection from 

 a silvered plane surface. Screens of various coloured 

 alcoholic solutions were employed, and the best results 

 were obtained when the screen absorbed all the luminous 

 radiations of the spectrum, allowing only the extreme rei* 



