March 21, 1895] 



NATURE 



487 



these elements — of which "argon" may be one — should exhibit 

 propertiesdiflferiDgchiefly in degree from the alternate palladiuai 

 and platinum triplets ; while hydrogen would appear as the 

 primarj- of both systems of elements. 



Dr. Gladstone's letter, which appeared in your issue of 

 February 21, admirably puts the reasons for preferring an 

 atomic weight of about 20 for argon to the higher number 

 which Lord Rayleigh and Prof. Ramsay are now disposed to 

 assign to it ; but Dr. Gladstone seemsto think that there is room 

 for only one element, whereas three are possible, as I pointed 

 out at the Oxford meeting, for the reasons given in the foregoing. 



It will be seen from the illustration that an element with an 

 atomic weight between 36 and 39 would belong to a third 

 system of elements. But the sole ground for concluding that 

 the atomic weight of argon lies between thcie points, is the 

 ratio of the specific heats as determined by Kundt and Warburg's 

 method. Lord Rayleigh and Prof. Ramsay found this ratio to 

 be nearly equal to that afforded by mercury gas, the molecule of 

 which is monatomic and density only half its atomic weight; hence 

 they conclude that the argon molecule is monatomie, and that 

 its density of nearly 20 represents but half the atomic weight. 

 Now, while any opinion on this point, coming from the dis- 

 tinguished discoverers of argon, is of the highest value, it seems 

 possible to attach undue weight to the very slender evidence 

 afforded by the specific heats, for mercury at present is the only 

 one of the known cases of monatomie elementarj' molecules in 

 which the ratio of the specific heats has been determined. But, 

 even admitting that the energy of the mercury and t'.ie argon 

 molecules is chiefly translational, it is still conceivable thit the 

 .irgon molecule includes two atomic vortices so closely inter- 

 linked as to have a common centre, and therefore to enable the 

 molecule to simulate a monatomie character. Such a structure 

 would lie consistent with great stability and, consequently, with 

 exceptional chemical indifference. J. Emerson Reynolds. 



Trinity College, Dublin, March 19. 



Variation in Caltha palustris. 



Reading the notice of Mr. Burkill's paper on " Variations 

 in Stamens and Carpels," in Nature of February 7 (p. 359), 

 I remembered the following notes on Caltha paluitris, which 

 my wife and I made at Corfe, Dorset, June II, 1891. 



C. paluitris: heads in pairs on a "dichotomously branching 

 stalk ; number of follicles in each head, counted in several 

 specimens, as follows : — 



7 follicles on one, 4 on the other, of a pair. 8 — 5> S — 7> 

 S— 6, 6—6, 6—7, 7—5, 9—9, 10—8, n— S, 9—6. 



Thus there is gieat variation. One stalk is longer than the 

 other, of a pair, and it is presumed that in every case the 

 shorter one flowers first. It will be noticed that in the above 

 eleven instances, only two had the same number offolbcles on 

 both stalks. Of the remaining nine, three had most follicles 

 on the longer of the stalks, and six had most on the shorter. 

 Those on the shorter stalk werelai^er than those on the longer, 

 presumably because older. 



A second memorandum gives the results of fifteen more 

 counts, all taken at random, thus ^L. = longer, S. = shorter 

 stalk) :— 



It accordingly appears that the later-flowering, longer-stalked 

 head produced more follicles in just half the number of cases 

 counted (13 out of 26), and the shoiter-stalked head had a 

 majority in only 5 cases, the remainder being equal. 

 < In a Bidots found at Barbadoes (West Indies), on July 6 of 

 the same year, there were similarly two heads, a long-stalked 

 and a short-stalked, the latter flowering first. It would be in- 

 teresting to get statistics of the numbers of akenes in the heads 

 in this. The species was not certainly determined, but it is of 

 the section of A', bipinnata. T. D. A. CocKERELL. 



New Mexico (U.S.-V.), February 24. 



NO. 1325, VOL. 51] 



DR. M. FOSTER ON THE TEACHING OF 

 PHYSIOLOGY IN SCHOOLS} 



THE teaching of science in schools has, it seems to 

 me, two uses. The first is what I may call the 

 " awakening " use. Many minds who feel no interest in 

 the ordinary subjects of school learning, to whom the 

 ordinary lessons appear as so much dull mechanical 

 work, are at once stirred to intellectual activity when the 

 teaching of this or of that science is presented to them. 

 The second use is the more distinctly " educational," 

 training use. 



The minds of the young being, happily, differently 

 constituted, one mind is especially " awakened " by one 

 branch of knowledge, another by another. One boy or 

 girl dates the beginning of his or her intellectual activity 

 from the day on which he or she had a first lesson in 

 chemistry. Another starts in the same way with botany. 

 And the number of those to whom physiology thus serves 

 as " awakening " knowledge, is, it seems to me, sufficiently 

 great to render it desirable, by the introduction of the 

 teaching of physiology into schools, to afford adequate 

 opportunities for its exercising this benefical effect. 



It follows that, taught from this point of view, phy- 

 siology should be taught as a new independent subject, 

 not demanding any previous knowledge ; it should be 

 presented as a wholly new field into which the natural 

 mind may wander at will without any restrictions as to 

 being qualified for entrance. It also follows that the 

 teaching must be of a most elementary kind, that as 

 much of chemistr)' or physics as is necessary for the 

 comprehension of the physiological matters should be 

 taught with the physiology, and, as it were, as a part of 

 it, the pupil being led into chemistry and physics by his 

 interest in physiology, and not being compelled to learn 

 the one for which he or she perhaps does not, at present 

 at least, care before beginning the other. 



The instruction given, however elementary it may be, 

 should consist in part of demonstrations and practical 

 exercises. I need not enumerate these in detail, but 

 they must necessarily be limited in scope ; the dissec- 

 tion of a rabbit or some other animal to show structure, 

 some little microscopic work, such as the microscopic 

 study of the blood and of a few tissues, the examination 

 of the structure and working of the heart, the mechanics 

 and elementary chemistry of breathing, and the like. 

 But all these demonstrations, like the rest of the teach- 

 ing, I may repeat, should teach so much of chemistry, 

 of mechanics, &c., as is needed, as a part of the 

 physiological lesson. 



As an "awakening" study, I am in favour of physi- 

 ology being very widely taught ; but, as almost neces- 

 sarily follows from the view on which I have been 

 dwelling, it ought not to be made a compulsory study. 

 Made compulsory, it would as an awakening study lose 

 much of its virtues. I do not hide from myself the fact 

 that the present gross ignorance which prevails among 

 most men and women as to the most elementary facts 

 concerning their own bodies is most undesirable, espe- 

 cially perhaps as regards women ; but I am most de- 

 cidedly of opinion that it is better to meet this evil by 

 encouraging the study of physiology than by making it 

 compulsory. 



Physiology, as a distinctly educational study, as a 

 training for the mind, is a very different matter ; and it 

 is, in my opinion, in this aspect unsuitable for schools. 

 The training for the mind which physiology affords is 

 one, I venture to think, of no small value, but is one 



t A short time .igo, on my consulting him on behalf of a committee 

 appointed by the Hcidmasters" Association, to draft nrgulations for major 

 scholarships' cxarainations, Prof. MichaeC Foster was good eno.ugb to give 

 me this statement of his opinion on the teaching of physiology ia schools — 

 .-V >ubject of great importance, but of great difficulty, regarding which much 

 misconception prevails : it appears to me to be so valuable, that I have 

 sought for and obtained his permission to publish it.— Hesrv E. Arm- 

 strong. 



