6i4 



NATURE 



[April 27, 189^ 



Timesy is to promote the systematic and consecutive gradation 

 of schools and universities, and to supplement the valuable 

 work of recent years in respect of technical instruction by an 

 effort to bring all effective schools and colleges, whether special- 

 ised or not, within a comprehensive national scheme. It is 

 thought that this "may be most economically done, with the 

 minimum of interference, centralisation, and narrowing uni- 

 formity, by the recognition and encouragement of existing 

 effective schools, and by using available resources under local 

 control mainly to facilitate the ascent of pupils from lower to 

 higher grades." Among the members of the committee are 

 Sir H. Roscoe, Sir P. Magnus, Prof. R. C. Jebb, Prof. Max 

 Miiller, and Prof. H. Sidgwick. 



To determine the light refraction of liquid oxygen, Herren 

 Olszewski, and Witkowski (Cracow Academy) have lately made 

 use of total reflection. The liquid was held in a metallic case 

 having windows, and a number of protective envelopes. Into 

 it dipped a double plate formed of two plane-glass plates, with 

 an air layer of o"oo6 mm. between, which could be turned from 

 without through a given angle. Monochromatic light was 

 introduced, and the refraction of the liquid determined by means 

 of the bright interference-fringes observed with the netting of 

 the telescope at the borders of the field of total reflection. The 

 relative index of refraction was found to be i "2232, and the 

 absolute coefficient i'2235 (Dewar and Liveing, with the 

 prism method, obtained i'2236). The same authors sought 

 also to determine light-absorption, using for the liquid a pro- 

 tected tube closed below with a glass plate, while another tube 

 with terminal glass plates, dipped in the liquid above, and 

 could be screwed up or down. A ray of light was sent through 

 from below, and passing through various thicknesses of 

 liquid (according to the position of the inner tube) was reflected 

 in a spectral photometer, and compared with a direct ray. For 

 the spectral region of most intense absorptionof the green yellow 

 (between \ = 577 and A. = 570), values between 84 and 89 per 

 cent, were obtained for the light passing through i mm. thick- 

 ness of oxygen; for the red absorption band 88. 



The question of the purity of ice consumed for alimentary 

 purposes in Paris has been lately before the Conseil de Salubrite 

 de la Seine {/iev. Sci,). This ice is of two sorts, manu- 

 factured and collected. The production of artificial ice is 

 about 27,000 tons a year, and of the "crop" of natural ice, the 

 lac Daumesnil at Vincennes yields about one-half (12,000 to 

 15,000 tons a year). The price of the manufactured ice is 

 eighteen to twenty francs a ton ; that of the collected ice three to 

 four francs. The demand in Paris is not wholly met from those 

 two sources ; and there is some ice imported from Sweden and 

 Norway, which is, naturally, dearer than the ice from lakes, &c., 

 jn France. Now the lake Daumesnil just referred to is polluted 

 on the one hand by the entrance of a sewer, and on the other 

 by an artificial stream from the plateau of Gravelle ; this stream 

 traverses the Bois de Vincennes, and in the fine season receives 

 all sorts of impurities from its banks. It is a question, therefore, 

 of interdicting the collection of ice from this lake. The sewer 

 it appears, might be suppressed, but the Administration cannot 

 touch the stream. It is proposed to limit the use of ice from 

 sources like this lake to applications in which the ice is not 

 brought into direct contact with the liquids or solids to be cooled, 

 and that when such contact takes place (as in cooling drinks) 

 artificial ice alone should be used, got exclusively from spring 

 water, or river water sterilised by heat. 



The Agricultural Department of New South Wales has been 



making a series of interesting and useful inquiries as to the plants 



most visited by bees in the various districts of the colony. Some 



of the results are set forth in the February number of the Depart- 



NO. 1226, VOL. 47] 



ment's Gazette. It has been clearly proved that the flora of 

 Australia includes honey-producing trees, shrubs, and plants of 

 a high standard of excellence ; the honey produced by bees in 

 the near neighbourhood of the forest being of the finest quality, 

 and having few (if any) faults. While a gum-tree is in bloom 

 the bee will pass over the most tempting plant in a garden and 

 wing its way to the borders of the bush ; but, on the other hand, 

 a field of maize in tassel is a source of the greatest pleasure to 

 the busy little workers, who swarm in countless numbers, collect- 

 ing the pollen so necessary for their wants. The plants which 

 next seem to have the greatest attraction are the fruit-trees, 

 familiarly called summer fruits. Clover (both white and red) 

 yields a large quantity of first-rate honey, and bees kept at places 

 where clover grows never fail to visit the modest flowers of the 

 plant ; dandelion, also, is a valuable honey-yielding flower, and 

 is noted in all districts from Albury to Tenterfield. As to the 

 size and colour of the flowers most affected by the bees, much 

 diversity of opinion exists among apiarists, and in the face of the 

 very conflicting replies, the Gazette thinks it would be vain to 

 try to determine what coloured flowers are most attractive. 



It is not, perhaps, generally known that the largest wine- 

 growing district in Germany is Alsace-Lorraine. According 

 to a report forwarded to his Government by the French consular 

 agent at Frankfort, while the Wiesbaden regency has only 

 7,300 acres planted with vines which in 1890 yielded 1,644,040 

 gallons, the Coblenz regency 18,950 acres, giving 3,755,22a 

 gallons, that of Treves 8,980 acres, giving 1,832,400 gallons, 

 Alsace-Lorraine alone contains 75,640 acres, the production of 

 which in 1890 was 16,999,000 gallons (6,429,740 gallons in 

 1891), a production which is chiefly consumed in the country 

 itself. According to the same authority (whose report is sum- 

 marised in the current number of the Board of Trade Journal) 

 the average annual production of wine in the whole world 

 during the five years from 1886 to 1890 is estimated at 

 2,811,600,000 gallons. In this production Italy figures for 

 690,008,000 gallons, Spain for 657,250,000 gallons, and France 

 for 606,562,000 gallons; that is to say these three countries 

 supply two-thirds of the total quantity produced. Germany, 

 with an average annual production of 51,705,610 gallons, only 

 occupies the tent h place among wine-growing countries. The 

 value of some of her wines partly compensates her, however, 

 for the relativ ely small quantity of her annual crop. 



The Imperia Forest School at Dehra Dun seems to be exer- 

 cising a remarkably wholesome influence on the native students 

 who attend its classes. Addressing the students at the recent annual 

 distribution of certificates and prizes, Sir E. C. Buck, secretary 

 to the Government of India in the Revenue and Agricultural 

 Department, said that the school had been a signal success in 

 the widest sense. The student who passed through a technical 

 school was usually fitted only for the technical profession which 

 he was taught at the technical school. But the Dehra School 

 teaching was of such a broad and useful character that he believed 

 its students, that is, the students who passed out of it success- 

 fully, would be more fit for any kind of work requiring originality 

 and practical treatment than the students of any school or college 

 in India. It was the only important educational institution in 

 India in which the student was taught more in the field and in 

 the museum than in the lecture room ; in fact in which he was 

 taught how to observe, and how to draw conclusions from obser- 

 vation. The consequence had been that the only signal instances 

 which had, to his knowledge, occurred of original research 

 leading to position and useful results being accomplished by 

 natives of India, had been those in which such results had been 

 produced by ex-students of the Dehra School. Only recently the 

 Government of India had been obliged to close apprenticeships 

 attached to the Geological Department, because natives of India 



