September 26, 1901] 



NA TURE 



54? 



and it is possible that some may be so minute that they can 

 never be seen. It has been observed that certain fluids derived 

 from the culture of micro-organisms may be filtered through 

 thick asbestos filters, so that no particles are seen with the 

 highest powers, and yet those fluids have properties that cannot 

 be explained by supposing that they contain toxic substances in 

 solution, but rather by the assumption that they contain a 

 greater or less number of organic particles so small as to be micro- 

 scopically invisible. I am of opinion, therefore, that it is quite 

 justifiable to assume that vitality may be associated with such 

 .small particles, and that we have by no means reached what may 

 be called the vital unit when we examine either the most minute 

 cell or even the smallest particle of protoplasm that can be seen. 

 This supposition may ultimately be of service in the framing of a 

 theory of vital action. 



Weismann in his ingenious speculations has imagined such a 

 vital unit to which he gives the name of a biophor, and he has 

 even attempted numerical estimates. Before giving his figures 

 let us look at the matter in another way. Take the average 

 diameter of a molecule as the millionth of a millimetre, and the 

 smallest particle visible as the 7i-,i,7^th of a millimetre. Imagine 

 this small particle to be in the form of a cube. Then there 

 would be in the side of the cube, in a row, fifty such molecules, 

 or in the cube 50 x 50 x 50 = 125,000 molecules. But a 

 molecule of organised matter contains about fifty elementary 

 atoms. So that the 125,000 molecules in groups of about fifty 

 would number --fir-" — 2500 organic particles. Suppose, as 

 was done by Clerk Maxwell, one half to be water ; there would 

 remain 1250 organic particles. The smallest particle that can 

 be seen by the microscope may thus contain as many as 1250 

 molecules of such a substance as a proteid. 



Weismann's estimates as to the dimensions of the vital unit 

 to which he gives the name of biophor may be shortly stated. 

 He takes the diameter of a molecule at ^irrrn^irosth of a milli- 

 metre (instead of the one millionth) and he assumes that the 

 biophor contains 1000 molecules. Suppose the biophor to be 

 cubical, it would contain ten in a row, or 10 x 10 x 10 = 1000. 

 Then the diameter of the biophor would be the sum of ten 

 molecules, or ^utj-J.imt!; x 10 = o-rnj's'T, ju or ^jjrrVtnrth of a milli- 

 metre. Two hundred biophors would therefore measure TjftrySrr, 

 or Tr.W 'cam. or I jn (micron = iTriruth mm.). Thus a cube one 

 side of which was I ji would contam 200 ■; 200 x 200 = 

 8,000,000 biophors. A human red blood corpuscle measures 

 about 77 (J. ; suppose it to be cubed, it would contain as many 

 as 3,652,264,000 biophors. 



Now if the smallest particle that can be seen (rtrjire'h mm.) 

 may contain 1250 molecules, let us consider how many exist in 

 a biophor, which we may imagine as a little cube, each side of 

 which is 7j7Tr7irr7,th mm. There would then be five in a row of 

 such molecules, or in the cube 5 x 5 x 5 = 125 molecules ; and 

 if the half consisted of water about sixty molecules. 



Let us apply these figures to the minute particles of matter 

 connected with the hereditary transmission of qualities. The 

 diameter of the germinal vesicle of the ovum is J.yth of a 

 millimetre. Imagine this a little cube. Taking the diameter of 

 an atom at itr-.n-nigth of a millimetre, and assuming that about 

 fifty exist in each organic molecule (proteid, Aic), the cube 

 would contain at least 25,000,000,000,000 organic molecules. 

 Again, the head of the spermatozoid, which is all that is needed 

 for the fecundation of an ovum, has a diameter of about tiJ-, 

 mm. Imagine it to be cubed ; it would then contain 

 25,000,000,000 organic molecules. When the two are fused 

 together, as in fecundation, the ovum starts on its life with over 

 25,000,000,000,000 organic molecules. If we assume that one 

 half consists of water, then we may say that the fecundated 

 ovum may contain as many as about 12,000,000,000,000 organic 

 molecules. Clerk Maxwell's argument that there were too few 

 organic molecules in an ovum to account for the transmission of 

 hereditary peculiarities does not apparently hold good. Instead 

 of the number of organic molecules in the germinal vesicle of 

 an ovum numbering something like a million, the fecundated 

 ovum probably contains millions of millions. Thus the imagina- 

 tion can conceive of complicated arrangements of these mole- 

 cules -suitable for the development of all the parts of a highly 

 complicated organism, and a sufticient number, in my opinion, 

 to satisfy all the demands of a theory of heredity. Such a 

 thing as a structureless germ cannot exist. Each germ must 

 contain peculiarities of structure sufiicient to account for the 

 evolution of the new being, and the germ must therefore be 

 considered as a material system. 



NO. 1665, VOL. 64] 



Further, the conception of the physicist is that molecules are 

 more or less in a state of movement, and the most advanced 

 thinkers are striving towards a kinetic theory of molecules and 

 of atoms of solid matter which will be as fruitful as the kinetic 

 theory of gases. The ultimate elements of bodies are not freely 

 movable each by itself ; the elements are bound together by 

 mutual forces, so that atoms are combined to form molecules. 

 Thus there may be two kinds of motion, atomic and molecular. 

 By molecular motion is meant " the iranslatory motion of the 

 centroid of the atoms that form the molecule, while as atomic 

 motion we count all the motions which the atoms can individually 

 execute without breaking up the molecule. Atomic motion 

 includes, therefore, not only the oscillations that take place 

 within the molecule, but also the rotation of the atoms about 

 the centroid of the molecule." ' 



Thus it is conceivable that vital activities may also be deter- 

 mined by the kind of motion that takes place in the molecules 

 of what we speak of as living matter. It may be different in 

 kind from some of the motions known to physicists, and it is 

 conceivable that life may be the transmission to dead matter, the 

 molecules of which have already a special kind of motion, of a 

 form of motion sui generis. 



I offer these remarks with much diffidence, and I am well 

 aware that much that I have said may be regarded as purely 

 speculative. They may, however, stimulate thought, and if 

 they do so they will have served a good purpose, although they 

 may afterwards be assigned to the dust-heap of effete specula- 

 tions. Meyer writes as follows in the introduction to his great 

 work on "The Kinetic Theory of Gases," p. 4: — "It would, 

 however, be a considerable restriction of investigation to follow 

 out only those laws of nature which have a general application 

 and are free from hypothesis ; for mathematical physics has won 

 most of its successes in the opposite way, namely, by starting 

 from an unproved and unprovable, but probable, hypothesis, 

 analytically following out its consequences in every direction, 

 and determining its value by comparison of these conclusions 

 with the result of experiment." 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Sir Philip M.\gnus will distribute the prizes to students of 

 the Morley Memorial College, Waterloo Road, on October I. 



The Report of the Board of Education, reviewing the pro- 

 ceedings of the Board for the year which ended with last year, 

 has been published as a Blue-book. Reference is made to the 

 Committee appointed to consider the best means of coordinating 

 the technological work of the Board with that at present carried 

 on by other educational organisations. The report of the Com- 

 mittee was received some time ago, and is now " under con- 

 sideration " It is to be hoped that the report will soon be 

 issued and action taken upon it. 



SCIENTIFIC SERIALS. 

 The American Journal of Science, September. — The dis- 

 charge current from a surface of large curvature, by John E. 

 Almy. It was found that the current discharging from a fine 

 wire to a concentric cylinder is given by the equation 



I = LaV(V - b)lr', 



where I is the discharge current, V is the potential difference 

 between the wire and cylinder, L is the length of the discharge 

 wire, r the radius of the cylinder, b the minimum potential 

 necessary to produce a measurable discharge, and a a constant 

 depending upon the size of the svire, the nature of the discharging 

 gas and the sign of the discharge. — On octahedrite and brookite 

 from Brindletown, North Carolina, by H. H. Robinson. — On 

 the behaviour of small closed cylinders in organ pipes, by B. 

 Davis. When small gelatine capsules or light paper cylinders 

 were placed in a stopped organ pipe, on sounding the pipe the 

 cylinders immediately moved to the middle of the stationary 

 loop and arranged themselves in rows across the pipe. The 

 effects produced were of the same nature as the Kundt dust 

 figures. — On a c;i;iium-tellurium fluoride, by H. L. Wells and 



1 Meyer, " Kinetic Theory of Gises." TraisLiud by Bayn-s, London, 

 1899, p. 6. 



