December 8, 1892] 



NATURE 



M3 



in its siead. The simple method of manufacture employed by 

 the natives is as follows : — 



The tree is felled to the earth and cut into small pieces, or, 

 more properly speaking, into chips. 



A large metal pot is partially filled with water and placed 

 over a slow fire. A wooden tub is fitted to the top of the pot, 

 and the chips of camphor wood are placed in this. The bottom 

 of the tub is perforated so as to permit ^he steam to pass up 

 among the chips. 



A steam-tight cover is fitted on the tub. From this tub a 

 bamboo pipe leads to another tub, through which the enclosed 

 steam, the generated camphor and oil flow. This second tub is 

 connected in like manner with a third. The third tub is divided 

 into two compartments, one above the other, the dividing floor 

 being perforated with small holes, to allow the water and oil to 

 pass to the lower compartment. The upper compartment is 

 supplied with a layer of straw, which catches and holds the 

 camphor in crystal in deposit as it passes to the cooling process. 

 The camphor is then separated from the straw, packed in 

 wooden tubs of 133^ lbs. each, and is ready for market. 



After each boiling the water runs off through a faucet, leaving 

 the oil, which is used by the natives for illuminating and other 

 purposes. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge.— Mr. W, Ridgeway, late Professor at Queen's 

 College, Cork, has been elected to the Disney Professorship of 

 Archaeology for the customary period of five years. Prof. Ridge- 

 way's recent work on the origins of weights and measures have 

 made him well known as a scientific archaeologist. 



Mr. R. T. Glazebrook, F.R.S., Assistant Director of the 

 Cavendish Laboratory, has been appointed a member of the 

 Financial Board ; Mr. Lewis, Professor of Mineralogy, and Dr. 

 Gaskell, F.R.S., have been elected members of the General 

 Board of Studies ; and Mr. E. W. MacBride, Scholar of St. 

 John's College, has been appointed Demonstrator in Animal 

 Morphology, in the place of Mr. J. J. Lister, of the same Col 

 lege. 



The Museums and Lecture Rooms Syndicate propose to intro- 

 duce the electric light into the dissecting-room of the Anatomy 

 school, the lecture room, and histology class-room of the De- 

 partment of Physiology, and the Philosophical Library, at an 

 expense not exceeding £\oo. 



By the death, on November 30, of Dr. F. J. A. Hort, Lady 

 Margaret Professor of Divinity, the University has lost not only 

 a great theologian, but a distinguished student of science. Dr. 

 Hort was second to Prof. Liveing in the Natural Sciences Tripos 

 of 1 85 1, the first ever held. He received the mark of distinction 

 in Physiology and in Botany. In 1856, and again in 187 1, he was 

 an examiner for Honours in this Tripos. Throughout his life his 

 interest in the scientific progress of the University was deep and 

 hearty. 



A Syndicate has been appointed to consider the whole ques- 

 tion of the times of holding Tripos examinations, and the 

 changes that would follow if these were altered. The disadvant- 

 ages of the present system, by which much of the benefit of the 

 Easter term and of the Long Vacation are lost to students and 

 teachers alike, have of late been forcibly brought before the 

 Senate. It is to be hoped that, by bringing about a rational 

 "Easter " or otherwise, the Syndicate's eflTorts may lead to a 

 reformation. 



SCIENTIFIC SERIALS. 

 American Meteorological fournal, November, 1892. — Wind 

 measurement by H. W. Dines. The two instruments generally 

 in use, viz. the Robinson cup anemometer and the pressure 

 plate, are both more or less unsatisfactory in obtaining the ex- 

 treme pressure. The wind never blows uniformly, whereas the 

 instruments are calibrated on the supposition that it does so. 

 And the method of exposure is often unsatisfactory ; any obstacle 

 to the free circulation of the wind either at the side or even behind 

 or below the anemometer, vitiates the results. The usual factor 

 k for conversion of velocity to pressure in the equation P = kv" 

 is too high. The value -005 was given originally in a book on 

 engineering, with a footnote stating that the experiments on 



NO. I 206, VOL. 47] 



which it rested were doubtful, but it has since been copied 



without the note. Recent experiments show that '003 is 

 probably more correct, but with such a varying element as the 

 wind, any factor is of little use in deducing extreme pressures 

 from velocity anemometers. Instruments of different sizes give 

 different results, and those calibrated by indoor trials give more 

 wind than those tested out of doors. In some respects it is 

 more desirable to register the pressure than the velocity, but a 

 pressure plate which is to register 30lb. per square foot is hardly 

 suitable to record so small a force as one ounce, so that on many 

 days no sign of motion is given. The author concludes from 

 many careful experiments that the tube form of anemometer is 

 most likely to give satisfactory results, as, apart from electricity, 

 it is the only kind in which the motion or pressure can be trans- 

 mitted to a distance without loss by friction. In this instrument 

 the registering apparatus is placed away from the part exposed 

 to the wind —The storms of India, by S. M. Ballou. In this 

 article, which is a continuation of previous papers, the author 

 treats of the storms which accompany the winter and summer 

 rains. — The first aerial voyage across the English Channel, by 

 R. de C. Ward. This voyage was successfully carried out by 

 Dr. Jeffries and M. Blanchard on January 7, 1785. The balloon 

 left Dover at ih. p.m., and descended a few minutes before 4h. 

 p.m., not far from Ardres. — On the production of rain, by Prof. 

 C. Abbe. The author reviews the natural process of the for- 

 mation of rain, viz. saturation by aqueous vapour, condensation 

 into visible particles, and the agglomeration of these into drops 

 large enough to be precipitated. The problem of artificial for- 

 mation of rain will be partially solved if some method is invented 

 to bring about a sudden formation of large drops out of the 

 moist air that exists between the small particles of every cloud. 



SOCIETIES AND ACADEMIES. 



Paris. 

 Academy of Sciences, November 28. — M. d'Abbadie in 

 the chair. — Note accompanying the presentation of a work on 

 the new methods of the " Meoanique Celeste," by M. Poincare. 

 —On the existence of distinct nervous centres for the perception 

 of the fundamental colours of the spectrum, by M. A. Chauveau. 

 If one goes to sleep on a seat placed obliquely in front of a 

 window which allows the light from white clouds to fall equally 

 on both eyes, the coloured objects in the room appear illuminated 

 by a bright green light during a very short interval when the 

 eyelids are opened at the moment of awakening. The pheno- 

 menon is not observed except at the moment of awakening from 

 a profound sleep. From this it is concluded that there are dis- 

 tinct perceptive centres for the green, and probably also for the 

 violet and the red. Of these, the green centres are those which 

 first regain their activity on awakening. — Note on the obser- 

 vatory of Mont Blanc, by M. J. Janssen.— On the laws 

 of expansion of liquids, their comparison with the laws 

 relating to gases, and the form of the isothermals of 

 liquids and gases, by E. H. Amagat. The substances 

 examined were water, ether, alcohol, carbon bisulphide, 

 hydrogen, nitrogen, air, oxygen, ethylene, and carbonic acid, 

 the pressures ranging from 50 to 3000 atmospheres, and the 

 temperatures from 0° to 200". For both liquids and gases, the 

 isotheimals present a slight curvature turned towards the axis of 

 abscissae. The angular coefficient increases with the tempera- 

 ture. This effect is specially pronounced in the liquids, where 

 it corresponds to a widening-out of the network, well exempli- 

 fied in carbonic acid, in the part corresponding to the lower 

 temperatures. This widening-out gradually disappears as the 

 temperature rises ; in the lighter gases, the variation with the 

 temperature is very small. —Observations of Holmes's comet 

 ("/"" 1892), made at the Pa-is Observatory (west equatorial), 

 by M. O. Callandreau. — On a remarkable solar protuberance 

 observed at Rome on November 16, 1892, by M. P. Tacchini.— 

 On universal invariants, by M. Rabut. — On straight-line con- 

 gruences, by M. E. Cosserat.— On the passage of a wave 

 through a focus, by M. P. Joubin. An apparatus for showing 

 the complementary character of transmitted and reflected 

 Newton's rings is mounted vertically, and illuminated by a 

 small bright point placed at a distance of i •20m. along the 

 axis of symmetry. On moving a microscope along the axis of 

 reflection the rings first appear with a black centre, which 

 changes into while at the first focus of reflection, and again into 

 black at the second. — On the depression of the zero, observed 

 in boiled thermometers, by M. L. C. Baudin. The secular 



