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NATURE 



[March 24, 1910 



Prof. Woodworth later, attaches to tests of the speed of 

 simple mental and motor performances, since, though the 

 mental process is . very, simple, some indication may be 

 afforded of the speed of brain : action. The reaction time 

 test has been measured • on representatives of a few races, 

 with the general result that the time consumed is about 

 the same in widely different groups. 



Chemical Regulation of the Processes of the Body. 



Prof. W. H. Howell, of the Johns Hopkins University, 

 delivered the presidential address in Section K (Physiology 

 and Experimental Medicine). He summarised the present 

 state of knowledge of the chemical regulation of the pro- 

 cesses . of the body by means of activators, kinases, and 

 hormones. The chief points touched upon are as given in 

 the following brief abstract. 



In recent years we have come to understand that the 

 c<jmple.\ of activities in the animal body is united into a 

 functional harmony, not only through a reflex control 

 exerted by the nervous system, but also by means of a 

 chemical regulation effected through the blood or other 

 liquids of the organism. Having referred to Brown- 

 S^quard's generalisation, according to which every 

 tissue' of the body in the course of its normal meta- 

 bolism furnishes material to the blood that is of import- 

 ance in regulating the activities of other tissues. Prof. 

 Howell said in recent years it has been re-stated in 

 attractive form by Schiefferdecker in his theory of the 

 symbiotic relationship of the tissues of the body. Accord- 

 ing to this author, we may conceive that among the 

 tissues of a single organism the principle of a struggle for 

 existence, which is so importsnt as regards the relations 

 of one organism to another, is replaced for the most part 

 by a kind of symbiosis, such that the products of meta- 

 bolism in one tissue serve as a stimulus to the activities 

 of other tissues. From many sides and in many ways 

 facts have been accumulating which tend to impress the 

 general truth that the co-activity of the organs and tissue;; 

 may be controlled through chemical changes in the liquid 

 media of the body as well as through nerve impulses, but 

 in physiology, at least, we owe the definite formulation 

 of this point of view to Bayliss and Starling. Starling's 

 convenient term of " hormone " as a general designation 

 for such substances has served to give a wide currency to 

 the conception. 



In treating this subject one must consider also the more 

 or less nearly related instances of combined activity of a 

 chemical sort which are expressed by such terms as 

 chemical activators, kinases, and . co-ferments. . These 

 terms, like that of hormone, are relatively new ; they have 

 b"en brought into existence by investigators to explain or 

 , to express special reactions connected with metabolism, and 

 particularlv with the action of ferments. The word 

 activator has reference to the fact, long known,, th.it the 

 ferments, or some of them at least, are secreted in an 

 inactive form, a proferment, which is activated or con- 

 verted to an active form by a reaction with some definite 

 substance produced elsewhere in the body. 



The term kinase is used at present in animal physiology 

 in connection with two reactions only. In both cases it 

 refers to an activating process where the . activator is. a 

 colloidal substance of unknown composition. 



In addition to the activators of the inorganic and the 

 colloidal tvpe, there is perhaps a third kind of activation 

 exemplified in the substances known as co-enzymes or co- 

 ferments. This term may be used to define that kind of 

 cooperative activity between an enzyme and some other 

 non-colloidal substance which we see illustrated in the in- 

 fluence of the bile salts upon pancreatic lipase. The 

 process differs from activation of a proferment to a ferment 

 only in that the combination of the enzyme with its 

 activator is dissociable instead of being permanent. By 

 dialysis or otherwise the co-enzyme can be separated from 

 the enzyme, and . the action of the two may be tested 

 separately or in combination. Starling defines hormones 

 as chemical messengers w'hich, formed in one organ, travel 

 in the blood stream to other organs of the body and effect 

 correlation between the activities of the organ of origin 

 and the organs on which they exert their specific effect. 

 Such substances belong to the crvstalloid rather than the 

 colloid class ; they therefore are thermostable, and do not 

 act as antigens when injected into the living animal. 

 NO. 21 08, VOL. 83] 



The substances of known composition which may be re- 

 garded as playing the rdle of hormones are few in number, 

 three or four at most, as follows : — first, the carbon dioxide 

 formed in the tissues, particularly in muscle during con- 

 traction ; secondly, the adrenalin of the adrenal glands, 

 which in some way, directly or indirectly, makes possible 

 the full functional activity of the involuntary musculature 

 of the body ; thirdly, the hydrochloric acid produced in th" 

 stomach, which stimulates the formation of secretin in th" 

 duodenal epithelium ; and, fourthly, possibly the iodo- 

 thyrin of the thyroid gland, with its dynamogenic effect 

 upon the neuro-muscular apparatus of the body. In addi- 

 tion, there are a number of hormones of unknown com- 

 position which have been either proved or assumed to 

 exist, and are held responsible for certain well-known 

 correlations of function. 



Method and Matter of Science. 



Under the title " Science as Subject-matter and as 

 Method," Prof. John Dewey, of Columbia University, in 

 his presidential address to Section L (Education), introduced 

 the question of how far the science teaching in schools 

 has up to the present been educational in the true sense. 



All, he said, who are much interested in securing for 

 the sciences the place that belongs to them in education 

 feel a certain amount of disappointment at the results 

 hitherto attained. The glowing predictions made respect- 

 ing them have been somewhat chilled by the event. Of 

 course, this relative shortcoming is due in part to the 

 unwillingness of the custodians of educational traditions 

 and ideals to give scientific studies a fair show. Yet in 

 view of the relatively equal opportunity accorded to science 

 to-day compared with its status two generations ago, this 

 cause alone does not explain the unsatisfactory outcom-'. 

 Considering the opportunities, students have not flocked 

 to the study of science in the numbers predicted, nor has 

 science modified the spirit and purport of all education in 

 a degree commensurate with the claims made for it. The 

 causes for this result are many and complex. One in- 

 fluential cause, the remedy for which most lies with scien- 

 tific . men themselves, is that science has been taught- too 

 much as an accumulation of ready-made material with 

 which students are to be made familiar, not enough as a 

 method of thinking, an attitude of mind, after the pattern 

 of which mental habits are to be transformed. 



The infinitely extensive character of natural facts and 

 the universal character of the laws formulated about them 

 is sometimes claimed to give science an advantage over, 

 literature; but viewed from the standpoint of education,! 

 this presumed superiority turns out a defect ; that is ^" 

 s.-iy, so long as we confine ourselves to the point of vii 

 of subject-matter. Just because the facts of nature a 

 multitudinous, inexhaustible, they begin nowhere and e: 

 nowhere in particular, and hence are not, just as fac: 

 the best material for the education of those whose liv 

 are centred in quite local situations and whose careers a 

 irretrievably partial and specific! If we turn from multi- 

 plicity of detail to general laws, we find, indeed, that the 

 laws of science are universal, but we also find that for 

 educational purposes their universality means abstractnesj 

 and remoteness. 



One of the most .serious difficulties that confronts thf 

 educator who wants in good faith to do something wortf 

 while with the sciences is their number and the indefinit* 

 bulk of the material in each. At times it seems as if th' 

 educational availability of science were breaking dowr 

 because of its own sheer mass. There is at once so mucl 

 of science and so many, sciences that educators oscillate 

 helpless, between arbitrary selection and teaching a littli 

 of everything. . Science teaching has suffered becaus' 

 science has been so frequently presented just as so niucl 

 ready-made knowledge, so much subject-matter of fact an( 

 law. rather than as the effective method of inquiry into an; 

 subject-matter. 



We define science as systematised knowledge, but th' 

 definition is wholly ambiguous. Does it mean the body i 

 facts, the subject-matter? Or does it mean the process- 

 by which something fit to be called knowledge is brougl 

 into existence, and order introduced into the flux of exper 

 ence? That science means both of these things w: 

 doubtless be the reply, and rightly ; but in the order bot 

 of time and of importance^ science as method preced- 



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