NATURE 



[May 



1913 



very coarse shingle one turns from the erosion hypo- 

 thesis, and the slightly pitted nature of the rock 

 surface suggests solution. Alex. Stevens. 



Geological Department, University of Glasgow, 

 May 6. 



The Mountains and their Roots. 



Major Cowie's letter in Nature of May 8 gives 

 the impression that I had the facts of the observa- 

 tions on the deflection of the plumb-line in 

 India before me, and that I made my assump- 

 tions as to relative densities, and the mode 

 of compensation by extension of depressed crust 

 beneath the plains, " suitably adjusted," so as 

 if possible to bring out the desired results. This was 

 not the case. I made the assumptions about relative 

 densities which seemed to be a priori probable; and 

 it will be seen from the diagram at p. 1S4 of my 

 "Physics of the Earth's Crust" that fifteen years 

 before I wrote the paper in the Phil Mag. I had 

 suggested that compressed mountains would be partly 

 supported by an extension of the depressed crust 

 beyond them. 



Should anyone be inclined to undertake the labour 

 ot calculating from my formulae, introducing fresh, 

 constants, or other distances, I would warn him that 

 in the Phil. Mag. there is a misprint. In the for- 

 mula for the plateau, after the first bracket, insert x. 



I am much pleased that after so long a time my 

 theories are under discussion, and I hope to come 

 well out of it. I am sending to the Geological 

 Magazine a reply to some remarks by Sir T. H. 

 Holland in that journal, and to this I would refer 

 your readers as more fully giving my views on some 

 of the points under discussion. O. Fisher. 



Graveley; Huntingdon, May q. 



An Application of Mathematics to Law. 



I have read Mr. Potts's letter in Nature of April 

 24, but am at a loss to understand the use to which 

 he would put his equations. 



If it be his object to find some equation giving 

 the validity of a patent or foretelling in any way the 

 probability of its being upheld in a court of law, he 

 has clearly failed to do anything of the sort. 



If his equation I = M + i is to be of any value, the 

 quantity i must have a fixed value greater than zero. 

 In fact, however, for any given patent, i may have an 

 infinite number of values, including zero, since each 

 person will have his own idea of the amount of 

 ingenuity that must be shown in the particular case 

 by the inventor. Thus the inventor will certainly put 

 a high positive value upon 1", while his opponent will 

 as certainly say that the value of i is zero. It is clear 

 that the value of > can only be finally settled when 

 the validity of the patent has been settled by the 

 House of Lords, and at this stage of a patent's career 

 it is scarcely necessary to have an equation to test 

 its validity. So far as the rest of his letter goes, he 

 seems to have chosen a rather complex method of 

 setting out a few of the chief principles of patent law. 

 R. Stafford Cripps. 



Fulmer, Slough. 



I did not imagine that my letter would be taken 

 as an attempt to supersede the present methods of 

 determining validity. I intended it as a contribution 

 to the theory which underlies the enormous volume 

 of our case-law on the subject. Surely, as in other 

 cases of the progress from empiricism to science, the 

 first step must be in the direction of mathematical 

 or symbolic expression of the facts. The value of 



V 1. 2272, VOL. 91] 



such a symbolism is twofold : first, as an aid to 

 precision of thought ; and second, as a preliminary 

 to generalisation. It is a vital principle of English 

 law that all decisions shall harmonise with precedents 

 as much as possible, and on this account alone any- 

 thing should be of value which assists in formulating 

 generalisations. We admit the value of theory in the 

 physical sciences, apart from immediate practical 

 results : why should an attempt to develop a theory 

 of law be condemned because it does not at once do 

 away with the functions of the judge? 



Mr. Cripps 's difficulty as to the value of i will not 

 be so great if the actual cases given in my letter are 

 studied. I may add here, however, that it is imma- 

 terial what this value is, provided that it is measur- 

 ably greater than zero. It is settled law that a 

 scintilla of ingenuity is sufficient to support a patent 

 for something new and useful (cj. Thompson v. Amer. 

 Braided Wire Co., in the House of Lords, and other 

 cases). I therefore employed this symbol merely to 

 indicate that there had to be some positive difference. 

 Harold E. Potts. 



University Club, Liverpool. 



SYNTHETIC BIOLOGY AND THE 

 MECHANISM OF LIFE. 



THE presidential address delivered by Prof. 

 Schafer to the British Association in 1912, 

 and the subsequent independent discussion at a 

 joint sitting - of two of the sections, served, as 

 was pointed out by Prof. Armstrong' in a paper in 

 Science Progress in October last, " as a useful 

 corrective to the wave of vitalism that has passed 

 over society of late years owing to the pervasive 

 eloquence of Bergson and other writers. " Prob- 

 ably the majority of those who have studied the 

 phenomena of life from the chemical side will 

 agree with Prof. Schafer in his dictum that "at 

 the best vitalism explains nothing," and accept 

 his opinion "that we may fairly conclude that all 

 changes in living substance are brought about by 

 ordinary chemical and physical forces." The 

 difficulty, however, lies in obtaining any satisfac- 

 tory information as to what are the actual chemical 

 or physical changes which occur in the real living 

 cells or tissues. Since this discussion was held 

 Prof. S. Leduc, of the School of Medicine at 

 Nantes, has published a monograph 1 in which he 

 approaches the problem from the novel point of 

 view which now for several years past has guided 

 his experiments and with which readers of his 

 "Mechanism of Life " will be familiar. 



It is impossible to do justice to the author's 

 arguments or make clear the proper value of his 

 demonstrations in .1 short article such as the 

 present, but this will at least serve to direct atten- 

 tion to a few of the very remarkable results that 

 he claims to have achieved, which, if verified, are 

 certainly of the highest significance to the student 

 of the phenomena of life. 



The basis of Prof. Leduc's work may be sum- 

 marised in his own words as follows: "It is in 

 the physico-chemistry of liquids that an explana- 

 tion of the phenomena of life is to be sought " : 

 and he develops his views largely by studving the 

 nature of diffusion in liquids and the phenomena 



By Prof. Ste'phane Leduc Pp. ii + 217 



