48 + 



NATURE 



June 8, 191 1 



Ixxvii., p. 1S8), while the following additional observations 

 liave been made. 



Distribution. — I found musical sand at intervals along 

 the shore for nfjorc than ten miles north of Barmouth, 

 at VVhitesands Bay, Pembrokeshire, and at the North and 

 South Sands, Tenby. This suggests that it is much more 

 widely distributed along the shores of the British Isles 

 than has hitherto been sup|)osed. 



Conditions affecting Pitch of Note. — I obtained the note 

 by plunging a flattish pestle into an evaporating basin 

 containing some of the sand, and there appears to be a 

 definite relation between the curvature of the vessel and 

 the pitch of the note produced. The following typical 

 numbers were obtained with vessels of different material, 

 which were approximately hemispherical in shape, the 

 same pestle being used in each case : — 



When round-bottomed glass flasks are plunged into a 

 milk-bowl containing sand, the pitch appears to depend on 

 the curvature of the flask ; e.g. flask 



R ^Ji; cm gives note m =2050 

 R' =42 cm gives note ;/' = fijo 



TJ'2 "^ 



— = 1-44 ;-;-,= 1-49 



Within certain limits, a change in the temperature, the 

 quantity of sand moved, or the gas present between the 

 sand particles, appears to have no appreciable effect upon 

 the pitch. E. R. Thomas. 



University College of Wales, Aberystwyth. 



The Protective Value of the Sticky Hairs on Young 

 Leaves and Shoots. 



It is often difficult to imagine, and still more so to 

 discover, the particular foes against which the hairs of 

 young plants are a defence. In the course of the last two 

 days I have noticed two instances in which the same foes 

 have been successfully vanquished by a similar device 

 on two widely different plants. The first instance was 

 afforded by plants of Salvia patens, which had been re- 

 moved from a cool frame to the shelter of a wall prior 

 to being planted out in the borders ; the second by the 

 young leaves and shoots of several species of Rhodo- 

 dendron growing in my garden. The hairs of both these 

 plants were abundantly laden with dead and dying hymen- 

 oplerous gall-flies of several different species (? o'f the 

 genus Andricus). I examined several individuals, and 

 found them invariably to be females. They were caught 

 bv the legs, wings, or indeed almost anv portion of the 

 body. I failed to discover anv insects other than the gall- 

 flies captured by these hairs; and yet there were a few 

 diptcr.Hi-. lli.s walking unconcernedly over the leaves, and 

 in no w-iy inconvenienced by the stickv hairs. The 

 evidence would seem to point to these 'hairs being a 

 special protection against gall-causing insects at a stage 

 when the tender leaves and . shoots would otherwise be 

 very vulnerable by these tiny creatures. 



„, , Oswald H. Lattkr. 



Charterhouse, Godalming. May 21. 



The Teaching of Science in Secondary Schools. 



TiiF. report of tlie Board of Education on the above 



subject (see Nature. May 4) contains manv expressions 



of opinion with which I hcartilv agree. But I must beg 



respectfully to differ from the' authors as regards the 



NO. 2 1 71, VOL. 86] 



limitations they propose to put upon the use of every- 

 day phenomena in science teaching. The report »ay« : — ^ 

 •' They should, of course, be introduced as illustrations, ' 

 that is to say, when, and only when, they may happen 

 to be wanted to give point to the teaching." This dog- 

 matic statement ignores the fact that many well-known 

 teachers strongly prefer the opposite mode of procedure. 

 Upon their view a practical problem should be made the 

 starting point, so that the development of the scientitic 

 method should follow instead of precede ; e.g. from a 

 study of the crane the class should discover the triangle 

 of forces. The main argument for this procedure is that 

 the boys actually want to know how a crane works, 

 whereas interest in abstract principles does not, as a rule, 

 outcrop until the age of sixteen or seventeen years. My 

 own experience is distinctly in favour of the appeal to the 

 utilitarian rather than to the, scientific motive, except in 

 the case of exceptional boys or of those above the age of 

 seventeen. Ci. 1 T ' 



Oaklcigh Park, N. 



June Meteors. 



Though the long days and twilight nights prevent much 

 attention being given to observations of shooting stars in 

 June, still, important met<x)ric events are liable to occur 

 in this month. The following are computed details of the 

 four most important meteor showers that take place during 

 the period June 9-30 in the present year : — 



Epoch June 8, ijh. (G.M.T.). twenty-sixth' 6rder of 

 magnitude. Principal maximum June 9, gh. ; secondary 

 maximum June 9, i9h. 40m. 



Epoch June 9, 6h., twenty-second order of magnitude. 

 Principal maximum June 10, 9h. 3Sm. ; secondary maxi- 

 mum June 10, igh. 40m. 



P2poch June 13, i2h. 20m., seventh order of magnitude. 

 Principal maxima June 12, jh., and June 12, i2h. 15m. ; 

 secondary maxima June 10, 23h. lom., and June 13, 

 i8h. 35m. 



Epoch June 14, 4h., eighth order of magnitude. Prin- 

 cipal maxima June 12, 23h. 20m., and June 13, oh. 5m. 



June 5. John R. Henry. 



Daylight and Darkness. 



I AGREE with Mr. W. T. Lynn that tlie article in Nature 

 of May II (p. 349) leaves "little to be said with regard 

 to the so-called Daylight Saving Bill " ; but there is one 

 remark in it to which exception may be taken. This is 

 the s'^atement (p. 350) that it is " easy " to alter one's 

 watch when travelling into a zone where different time 

 is kept, if by " easy " is meant " not inconvenient." All 

 travellers must have found the inconvenience of the change 

 of time, even when reduced to a minimum through the 

 change being an exact hour. Some inconvenience is un- 

 avoidable in travelling, but it is, of course, absurd to cause 

 this inconvenience unnecessarily as the " Daylight Saving 

 Bill " proposes. The inconvenience is such that in a 

 journey to India I found it best never to alter my watch 

 at all. it being simplest to keep to Greenwich time, and 

 mentally make the allowance for local time. 



T. W. Backhoi -! 



West Hendon House, Sunderland, June i. 



HEREDITY AND DESTITUTION. 



DURING the past week a conference has been 

 sittiiifj to consider possible means for the pre- 

 vention of destitution. A general inaug^ural meeting, 

 took place on May 30, at the Albert Hall, and sec- 

 ti)onal meetint^^s were held on several davs at Caxton 

 Hall. 



Mr. A. J. Balfour, who delivered the openine ad- 

 dress at the general meeting, struck a note of which 

 echoes were heard throughout the cong^ress. He 

 devoted much attention to the bearing of heredity on 

 destitution, and to the influence of the present selec- 

 tive fall in the birth-rate on the average economic 

 efficiency of the nation. 



Although Mr. Balfour held that some supposed. 



