September 15, 1923] 



NA TURE 



407 



and custom will give right : It is easier to deny in 

 the beginning than aften\-ard. 



"It is a fundamental rule of the Society not to 

 meddle with religion ; and the reason is, that we may 

 give no occasion to religious bodies to meddle with us. 



" The Society for Promoting Christian Knowledge, 

 have a splendid title, but we are to regard not names, 

 but things. If all their members are not men of 

 exemplary lives and conversation, some of them, by 

 misdemeanors, may bring reflections upon us ; and 

 why should we run the hazard ? 



"If we comply, we may dissatisfy some of those 

 that are against it ; especially those that are of other 

 religions, and make them leave our meetings, which 

 are already too thin. 



" There are many vestries in London ; and it is 

 more proper for a religious society to meet in a vestry 



or than in the house of a society which is mixed 



of men of all religions, and meddles with none. 



" Those of the Christian Society have dining rooms 

 of their own, and may lend them by turns to their 

 meetings. And the tenth commandment is, ' Thou 

 shalt not covet thy neighbour's house.' 



" This proposal can be of no advantage to us ; but 

 may prove disadvantageous ; and we have, all of us, 

 at our admission, promised, under our hands, to 

 consult the good of the society ; and ought not to 

 break the fundamental covenant upon which we were 

 admitted." 



Mechanism of Stomatal Movement in 



Plants. 



T T has been generally recognised for a long time 

 ^ past that the stomata of the leaf opened when 

 more water was absorbed by the guard cells and 

 closed when water passed from the guard cells into 

 the surrounding tissues. It is also frequently 

 assumed that the mechanism by which this water 

 exchange takes place must be associated with the 

 presence of green chloroplasts in the guard cells, the 

 other epidermal cells being usually free from chloro- 

 phyll. 



The mechanism by which the osmotic concentra- 

 tion of the cell sap of the guard cell is controlled 

 has, however, remained obscure ; of late years ex- 

 perimental work has thrown light upon this problem, 

 and a valuable summary of this work is given by 

 Friedl Weber in Die Naturwissenschaften, Vol. ii. 

 Heft 17, April 27. Lloyd's work had shown that the 

 movement of the guard cells is not connected with 

 the direct photosynthesis of carbon dioxide by the 

 guard cells, the cells around the closed stoma at 

 night being packed with starch, while in the early 

 morning, in daylight, the starch rapidly hydrolyses 

 and the stoma opens. 



Iljin's series of papers now suggest that the vary- 

 ing activity of diastatic enzymes under different con- 

 ditions are intimately associated with the stomatal 

 mechanism. Iljin showed that with stomata closed 

 the guard cells were usually full of starch, the starch 

 disappearing as the stomata open. Further experi- 

 ments showed that sodium and potassium salts 

 accelerated starch hydrolysis, while calcium salts 

 !>revented it ; inorganic anions produced less effect, 



it citrates and acetates exerted considerable effect. 



The effect of the various salts upon the reaction 

 of the cell has to be carefully considered, the slightest 

 increase in hydrion concentration favouring starch 

 hydrolysis and stomatal opening; the slightest de- 

 crease, starch accumulation and stomatal closure. 

 The reaction of a stoma to these various factors 

 differs with the plant, halophytes, for example, show- 



i^ themselves very insensitive to changes in salt 



NO. 281 I, VOL. I I 2] 



concentration, whUe a plant like Rumex acetosa, with 

 very acid sap, is especially sensitive. It is clear that 

 our conception of the mechanism of control of stomatal 

 aperture will require re-examination in the light of 

 this interesting work. Thus Linsbauer's observations 

 on the movement of the guard cells with change of 

 light intensity, or with alterations in the carbon 

 dioxide content of the air, may find their explanation 

 in the consequent alteration of reaction in the cell 

 sap of the guard cell. 



University and Educational Intelligence. 



Durham. — As a result of the recent decision of the 

 council of Armstrong College to build a College 

 Library, all practising members of the Northern 

 Architectural Association, and a few architects in 

 other parts of Great Britain, were invited to submit 

 competitive designs for the building. The first 

 premium has been awarded to Mr. A. Dunbar Smith, 

 who has been appointed architect of the library, and 

 work will proceed forthwith. The building will con- 

 sist of a reading-room seating 122 readers, storage 

 space for 175,000 volumes, with accommodation for 

 55 research students, administrative rooms, and 

 photographic laboratory, and is so designed that 

 additional storage space for 60,000 volumes may be 

 added when required. 



Manchester. — On Tuesday, September 11, Sir 

 George Beilby opened the new buildings to be occupied 

 by the Department of Metallurgy in the University. 

 Although founded in 1906, the home of the Depart- 

 ment has so far been merely a few laboratories loaned 

 by the Chemistry Department. Especially from the 

 point of view of the research workers this arrange- 

 ment was far from satisfactory. In the new buildings 

 four research laboratories will be available, in addition 

 to general laboratories for pyrometry, mechanical 

 testing, and metallography. A small foundry and 

 machinery room together with the heat-treatment 

 laboratory will further offer facilities both for teaching 

 and research which have hitherto been incompletely 

 available. The main general laboratory, named after 

 Henry Cort, the eighteenth-century metallurgist, the 

 inventor of rolling metals in grooved rolls and a 

 pioneer in connexion with the puddling process, is 

 well equipped for the determination of the physical 

 properties of metals at temperatures above the normal. 

 A small laboratory is devoted to fuel examinations, 

 so that it may be claimed that the new buildings 

 afford excellent facilities for both teaching and 

 research in metallurgy, metallography, and fuel. 

 Since 19 10 sixty papers have been published in 

 recognised journals dealing with the research work 

 done in the Department. Among the more important 

 of the subjects investigated may be cited work on 

 high-speed steel, the growth of cast iron on repeated 

 heatings, chromium steels, including stainless steel, 

 the influence of gases on iron and steel, the production 

 of high-pressure castings, and the hardness and elastic 

 limits of metals both at and above room temperatures. 

 On the foundation laid by Prof. H. B. Dixon and 

 continued by his successors in the chair of metallurgy. 

 Profs. H. C. H. Carpenter and C. A. Edwards, an edifice 

 worthy of their labours has at length been erected. 



The following free public Qresham lectures will 

 be delivered at Gresham College, Basinghall Street, 

 E.C., at 6 o'clock on the dates given : Astronomy, by 

 A. R. Hinks, on October 9, 'lo, 11, and 12; Physic, 

 by Sir Robert Armstrong- Jones, on October 16, 17, 

 18, and 19; and Geometry, by W. H. Wagstaff, on 

 October 23, 24, 25, and 26. 



