404 



NATURE 



[January 24, 19 18 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for 

 opinions expressed by his correspondents. Neither 

 can he undertake to return, or to correspond with 

 the writers of, rejected manuscripts intended for 

 this or any other part of Nature. No notice is 

 taken of anonymous communications.] 



Ice Thistles. 



In Nature for January n, 1917, Dr. R. T. Gunther 

 directed attention to the beautiful form assumed by 

 the air bubbles which separate from water which is 

 allowed to freeze in a small jar. I was able in the 

 issue of February 15 last to describe some larger 

 i'xamples of the same phenomenon. 



On December 26 last the ice on the Legs of Mutton 

 Pond in Bushey Park and on the Cardinal's River, 

 which flows through it, was very clear, and the 

 bubbles, separated in the course of freezing, were very 

 obviously arranged along lines of flow. In the pond 

 they converged towards the outflow sill communicating 

 with the river, and in the river they were in lines 

 parallel to the banks. In one or two cases where the 

 stem of a weed was frozen into the ice the course of 

 the water as diverted on either side of it was made 

 clear by curves of bubbles. 



On the following day I managed to melt some of the 

 ice over its own water, by the heat of the hand, in a 

 bottle with the bottom cut off and a graduated tube 

 inserted in the neck. Knowing the capacity of the 

 bottle,, and measuring the volume of water required 

 to fill it when packed with ice, I got a fairly accurate 

 measurement of the ice. The bottle was then put In a 

 tin can with water, and the gas as it was liberated 

 from the ice passed into the graduated tube. 



From 104 c.c. of ioe I obtained i-86 c.c. of gas, of 

 which 076 c.c. was Absorbed by alkaline pyrogallate. 

 A litre of this ice would therefore yield 7-18 c.c. of 

 oxygen and 10-30 c.c. of nitrogen and argon, apart 

 from any gases which might still be dissolved in the 

 ice. The pond water under the ice yielded 31-2 parts 

 of solid residue on evaporation and 2-35 parts of 

 chlorine, and the melted ice (after settlement of sus- 

 pended matter) 100 oarts and 0-39 part respectively. 



That the salts yielded by melting ice are no real part 

 of it, but are derived from watery inclusions only, can 

 be shown very beautifully by carrying out Dr. 

 Gunther's- "ice-thistle" experiment with water tinted 

 with methylene-blue, or, better, potassium perman- 

 ganate. A characteristic " thistle " with white silvery 

 rays of air bubbles in a clear hyaline, and a central 

 blue or crimson "egg" of solution much deeper in 

 colour than the original solution, is obtained. This 

 becomes smaller as freezing proceeds. Sometimes 

 coloured veins are seen in the colourless ice, and some 

 of the air bubbles are associated at their inner ends 

 with coloured liquid. This experiment, as showing 

 the separation of dissolved matters, both gases and 

 solids, when a portion of a liquid freezes, seems to be 

 worth noting, especially as it also Illustrates the course 

 of the freezing. ' J. H. Coste. 



Teddlngton, January 11. 



SCIENCE IN INDUSTRIAL RECON- 

 STRUCTION. 



Tl 7"ITHIN the past year or two, frequent refer- 

 ♦^ * ence has been made in these columns to 

 measures of natiopal reconstruction recommended 

 by various committees. There is now a Ministry 

 of Reconstruction, and its advisory committees 

 NO. 2517, VOL. 100] 



are so many that we have almost lost count of 

 them; whilst scarcely a week passes without a 

 report appearing^ in which promising^ schemes of 

 industrial organisation and development are pro- 

 jected. The material value of scientific research 

 is usually gfiven due recognition, at any rate on 

 paper ; and if we may take these signs as an 

 earnest of things to come, they give us confidence 

 in a progressive future based upon a just and 

 intimate co-ordination of brain and hand. 



Though manual and mental workers are often 

 considered to belong to different classes, and an 

 indefensible social distinction is usually made 

 between them, no such separation can be recog- 

 nised in scientific fields, where fine manipulation, 

 and skill in the use of instruments, are frequently 

 as valuable as fertility in idea and ingenuity in 

 design. Industrial advance seems, indeed, to 

 j depend upon three main factors, in all of which 

 j brain and hand are related, though in different 

 degrees. First there is the creative investigator 

 whose work reveals new properties and relation- 

 ships ; then comes the inventor or industrial re- 

 searcher who seeks to apply knowledge to useful 

 ends ; and when a practical process or machine 

 has been devised, the artisan is needed to make 

 it fulfil its technical purpose. Each of these three 

 classes has an essential place in national polity ; 

 and the correlation of their interests and activities 

 must be the chief aim of all schemes of recon- 

 struction. 



Several recent reports and manifestoes are con- 

 cerned with the combination of these different 

 groups. The Interim Report on Joint Standing 

 Industrial Councils (Cd. 8606, price id. net), sub- 

 mitted to the Prime Minister by a sub-committee 

 of the Reconstruction Committee, and referred to 

 as the "Whitley" report, suggests the establish- 

 ment of district and national councils which 

 should deal, among other matters, with technical 

 education and training and with industrial re- 

 search and the full utilisation of its results. There 

 has lately been established, under the presidency 

 of Sir Wilfrid Stokes and the chairmanship of 

 Mr. Ernest J. P. Benn, an Industrial Reconstruc- 

 tion Council to encourage the formation of 

 national industrial councils in the several trades, 

 and to offer guidance when necessary. Moreover, 

 the draft constitution of the new Labour Party, 

 which has just been submitted to the Nottingham 

 Conference, has in the forefront of the party 

 objects, " to secure for the producers by hand or 

 by brain the full fruits of their industry"; and thc 

 secretary of the party, the Right Hon. Arthur 

 Henderson, informs us that "the term 'pro- 

 ducers by hand or by brain ' would include scien- 

 tific workers if they are prepared to accept our 

 constitution and programme. The object in widen- 

 ing the basis of the party is to obtain the assist- 

 ance of all who depend upon their own exertions, 

 for the means of livelihood." 



Scientific workers are thus offered facilities for 

 representation in Parliament if they are prepared 

 to associate themselves with the Labour Party. 

 Much can be said in favour of such co-operation. 



