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NATURE 



[November i8, 1920 



Observations over Kurope, the only part of the world 

 where they are numerous enough for the purpose, 

 have also shown a most extraordinarily close correla- 

 tion between the temperature and pressure of the air 

 in the upper part of the troposphere, many of the co- 

 efficients exceeding 090. These facts must be 

 reckoned \^ith in any theory about the formation 

 of cyclones. 



My own belief is that pressure differences originate 

 in the upper half of the troposphere from variations 

 in the strength of the surrounding winds. Being 

 given the means of originating and maintaining a 

 difference of pressure at about the height of 9 km., 

 the rest of the phenomena follow readily. The dis- 

 tribution of temperature, the high positive correlation 

 Jbelow and the negative correlation above, and the rise and 

 fall of the tropopause between cyclone and anticyclone 

 are all explained by the vertical motion of the air that 

 would naturally follow from the distribution of 

 pressure. W. H. Dines. 



Benson, November 12. 



Physiological Method as a Key to the Causation of 

 isle of Wight Disease In Bees. 



In the summer of 1918, while working with Prof. 

 L. Hill and JNlr. T. A. Webster on gas research, I 

 advised Dr. John Rennie, of the natural history 

 department of the University of Aberdeen, that a 

 physiological study of metabolism in healthy bees and 

 in bees known to be suffering from symptoms of Isle 

 of Wight disease should be undertaken, making use 

 of oxygen and carbon dioxide determinations. As a 

 corollary, an investigation into the temperature of 

 bees, healthy and unhealthy, was also indicated. 



In the summer of 19 19 it was found that apparently 

 bees infected with Isle of Wight disease consumed in 

 a given time much less oxygen than healthy controls. 

 This observation was not reported to me until July, 

 1920, when I was able at once to draw the conclusion 

 that the symptoms of Isle of Wight disease were due 

 to blocking of tracheal tubes and anoxaemia. Loss 

 of the power of flight was to be expected, as the 

 co-ordinating nervous mechanism and the musculature 

 involved were deprived of their proper oxygen supply. 



Had I been made acquainted with the results of a 

 research I had advised, or had the investigator been 

 able to draw a very simple phvsiological conclusion 

 from the data, whether the data were correct or 

 erroneous, the discovery of a parasite as the blocking 

 agent or disturbing factor in tracheal tubes would 

 have been the natural consequence. 



In 1920 this parasite was discovered by anatomical 

 study, and its presence as fhe agent causing the 

 disease is announced in the Press as the outcome of 

 the researches of Dr. John Rennie, Mr. P. Bruce 

 White, and Miss Elsie J. Harvev. 



It will be noted that the physiological method of 

 investigation could have led equally surely to the 

 discovery of the parasite and to the interpretation of 

 the symptoms. James M. McQueen. 



Halesowen, November 5. 



Luminosity by Attrition. 



I AM very glad that Sir Ray Lankester has again 

 directed attention to this phenomenon. Bv a slip of 

 the pen he says (November 4, p. 310) "quartz pebbles" 

 in his first paragraph and in the heading. My object 

 in writing is to say that these pebbles may be found 

 on any shingle beach, and may be known bv their 

 translucent appearance under a "rotten" (or pitted) 

 exterior. They are ^aXe brown, and, when drv. look 

 like lumps of derelict toffee. But on the shingle 

 beaches of South Devon (notablv the " Budleigh 

 Salterton Pebbles"), the Chesil Beach, and the Suffolk 

 NO. 2664, VOL. 106] 



coast (notably at Aldeburgh) practically every pebble 

 on the beach will "flash." 



It is much to be desired that some mineralogist 

 should take up the intensive study of flint, chert, and 

 quartzite. I may mention that for many years I have 

 stored every "peculiar" flint pebble I have come 

 across, and my entire collection is at the service (as a 

 gift) of any museum worker who cares to undertake 

 the study. Edward Hekon-.Xllen. 



Large Acres, Selsey Bill, Sussex, 

 November 12. 



The recent letters in Nature from Lieut. -Comdr. 

 Damant and Sir E. Ray Lankester recall some 

 observations made in 1916 in collaboration with my 

 friend and former headmaster, the late Mr. W. P. 

 Workman, who first directed my attention to this 

 interesting phenomenon. Specimens of translucent 

 quartz from a quarry about three miles from Tintagel, 

 North Cornwall, give the characteristic orange- 

 coloured light in broad daylight and the peculi.jr 

 smell. This triboliiminescence of quartz was observed 

 by Du Fay in 1735, and about 1748 Delius mentioned 

 the sulphurous smell which accompanies the glow 

 when quartz is rubbed against quartz (Kayser, Bd. iv , 

 pp. 614, 617; Winkelmann, Bd. vi., p. 809). 



The following observations present, I believe, some 

 points of novelty : (i) Luminescence is produced when 

 quartz is rubbed by any material, such as topaz or 

 sapphire, which is harder than itself. Dr. Gordon, 

 head of the geological department of King's College, 

 London, kindly lent a number of minerals for the 

 purpose of this test. Ordinary steel, which falls 

 below quartz in the scale of hardness, does not cause 

 the glow. (2) Fused quartz, as sunnlied by the Silica 

 Syndicate, gives a very fine effect. I have on several 

 occasions shown this as a lecture experiment bv 

 rubbing together two tubes of transparent fused 

 silica. In this connection the observation of Lord 

 Rayleigh (Nature, vol. civ., p. 153, 1919) that "silica 

 glass " possesses a remarkable cnistalline or quasi- 

 crystalline structure is of special interest. (3) The 

 tubes of fused quartz when rubbed together give the 

 same peculiar odour as ordinarv quartz pebbles. 



It should, therefore, be possible to carry out an 

 experiment of the kind suggested by Sir E. Rav 

 Lankester by grinding the interior of a quartz vessel 

 which might be fiighly evacuated or contain 

 suitable liquid or gaseous reagents. According to 

 Lord Ravleigh's experiments (Royal Societv, February 

 27, 1919), the clearest and whitest quartz has some 

 power of scattering light, though much less than 

 that of glass or liquids. This small scattering is con- 

 sidered to be due to inclusions, as in the case of 

 visibly smoky or yellow quartz. Mav not the presence 

 of minute diffused metallic particles, or perhaps 

 particles of silicon itself, be the cause of the various 

 phenomena under discussion? H. .S. .\U-EN". 



The University, Edinburgh. 



Contractile Vacuoles. 



There is no doubt that the explanation of the pro- 

 duction of these vacuoles as given in Nature of 

 November 11 by Prof. Henry H. Dixon is the correct 

 one. It may perhaps be of interest to Prof. Dixon 

 to refer to a paper by W. Stempell published in 

 1914 in Zoolog. Jahrb.,' Aht. allg. Zoo], u. Physiol, 

 der Tiere (Bd. 34, iii., p. 437), where the same view 

 is put forward. I believe that this journal is not 

 very accessible — a fact which doubtless accounts for 

 its having been overlooked. I may say that it is mv 

 custom to teach this view, and a brief account will 

 be found on p. 162 of mv " Principles of General 

 Physiology." W. M. Bayliss. 



