March io, 1898] 



NA TURE 



453 



solely from his law of ancestral heredity, the whole theory of 

 heredity becomes simple, luminous, and well in accordance with 

 such^quantitative rneasiiremeiits as have so far been made. 



It is possible to somewhat generalise the law of ancestral 

 heredity, Modifying Mr. Galton's definition of midparent, a 

 conception is formed of the mid-jrth parent, a sort of mean of 

 the ancestry in the Jth generation, and the contribution of this 

 mid-Jth parent to the offspring is assumed to have a constant 

 ratio to that of the mid-(f + i)th parent, whatever be the value 

 of s. With this simple; law the whole of heredity is found to 

 depend upon a single constant 7, termed ih^ coefficient of heredity . 

 y may vary from organ to organ and from race to race. It may 

 itself be subject to selection, if heredity be not looked upon as a 

 priori given and antecedent to any evolution by natural selection. 

 In Mr. Galton's statement of the law, 7=1. This may really 

 be the case, but it is not necessary to the theory, and it is not 

 required by any facts as yet observed. 



Given this simple law of ancestral heredity, there flow from it 

 the following results : — 



(i) Heredity between any grade of individual kinship. 



(2) The value of the stability that results from any long or 

 short process of selective breeding, and the variability of the 

 breed so established. 



(3) The law of cross heredity, i.e. the degree of relationship 

 between two different organs in kindred. 



(4) That panmixia without active reversal of natural selection 

 does not lead to degeneration. 



It may be of interest to add that since the law of ancestral 

 heredity allows for the variability of each individual ancestor 

 from the ancestral type, giving that variability its share in the 

 heritage of the ofiFspriag, it is inconsistent with Weismann's 

 theory of the germplasma. It does not, of course, answer one 

 way or the other the question as to the inheritance of acquired 

 characters. 



Thus Galton's law of ancestral heredity leads to, what has not 

 hitherto existed, a rounded and comprehensive theory of heredity. 

 It describes with surprising closeness all facts so far quantitatively 

 determined, and opens up a wide range of conclusions which 

 await testing by fresh data. Should those data be in agreement 

 with its predictions, then the law of ancestral heredity will in 

 the future play as large a part in the theory of evolution as the 

 law of gravitation has played in planetary theory. It is the 

 quantitative basis on which Darwinism, the evolution of species 

 by natural selection combined with heredity, will then be placed ; 

 and at one stroke it will clear away a veritable jungle of semi- 

 metaphysical speculations and hypotheses, and this for the simple 

 reason that it is based upon quantitative observations and not on 

 verbal subtleties. It will be difficult, perhaps, to make people 

 realise that there is a science of heredity, simple and consistent, 

 in existence ; yet even at the present time it is the number of 

 observers and experimenters, rather than the science, which needs 

 to be strengthened. 



"The Magnetic Properties of almost pure Iron," By Ernest 

 Wilson. 



In the Siemens Laboratory, King's College, London, a series 

 of experiments were carried out on a ring of iron containing 

 only about '12 per cent, impurities. The ring was tested as 

 received and after careful annealing. As received, the magnetic 

 hysteresis loss was slightly greater than in an exceptionally good 

 sample of transformer plate examined by Ewing. After an- 

 nealing the hysteresis loss was still slightly inferior to the 

 Ewing specimen, but an exceptionally large value was obtained 

 for its maximum permeability ; n being 5490 for B = 9000 C.G.S. 

 units per square centimetre. The coercive force for maximum 

 B = 15,720 is I '13 C.G.S. units. Further experiments were 

 carried out to investigate the apparent magnetic instability of 

 the specimen. The.author finds that this eflFect cannot be ac- 

 counted for by the self-induction of the ring, nor the time taken 

 for the current to rise to its, full value. A method is explained for 

 testing the rapidity \yith which the current rises to its maximum 

 value. The propagation of, magnetism in, the ring as affected 

 by induced currents is dealt with, and it is pointed out that 

 these may have an effect on the observations, although it is 

 difficult to account for such times as five and ten seconds, unless 

 the molecule itself be considered. It is deduced from the ex- 

 periments that the amplitude of induction might not be so great 

 for high frequency and small induction density, which would 

 be of importance in the case of transformer cores if it existed. 

 Reference is made to experiments with alternate currents which 



NO. 1480, VOL. 57] 



show no such diminution ; but it is pointed out that experi- 

 ments with alternate currents would be difficult to carry out, on 

 account of the necessary accurate control of the magnetising 

 force. 



"The Kelvin Quadrant Electrometer as a Wattmeter and 

 Voltmeter." By Ernest Wilson. 



Two of these instruments were available to the author 

 when carrying out the series of tests described in this 

 paper. He. was thus able to use one in connection with 

 a revolving contact-maker to determine the instantaneous 

 rate at which work was being done by alternate currents 

 while testing the other as a direct-reading wattmeter. The 

 author finds that by the contact- iraker method he gets good 

 accuracy by taking ten positions of the contact-maker per half- 

 period, and calculating directly from the figures without inte- 

 grating the curves. When current and potential were in phase 

 an agreement within i or 2 per cent, was obtained between the 

 watts calculated this way and the product of the square root 

 of mean square values given by an ammeter and voltmeter. 

 The use of a small mallet for gently tapping the electrometer 

 base is recommended to overcome the effects of viscosity of the 

 acid in the electrometer when this is old, although in the new 

 form of instrument the viscosity gives little or no trouble, 

 since the sensibility is not so great. The wattmeter constant 

 was determined for various frequencies, phase differences, 

 amplitudes, wave forms, and the results show that the Kelvin 

 quadrant electrometer can be used with accuracy as an alternate 

 current wattmetter, but that it is necessary to make sure that 

 within the range of potentials applied Maxwell's formula is 

 verified. Two methods of doing this are explained. The 

 author observed a potential of nearly half a volt, due to the 

 revolving contact- maker alone, when directly placed across the 

 electrometer ; but this inductive effect disappeared when a 

 capacity, large compared to that of the instrument, was placed 

 across it. The paper concludes with an interesting note on a 

 manganin strip used for comparatively large currents. The 

 experiments were carried out in the Siemens Laboratory, 

 King's College, London. 



February 3. — " The Pharmacology of Aconitine, Diacetyla- 

 conitine, Benzaconine and Aconine, considered in relation to 

 their Chemical Constitution." By J. Theodore Cash, M.D., 

 F.R.S., and Wyndham R. Dunstan, M.A., F.R.S. 



In this research the pure alkaloids aconitine, benzaconine and" 

 aconine derived from A. Napellus, and an aconitine derivative, 

 diacetylaconitine were examined with reference to their action 

 upon warm- and coldblooded animals, a similar series of 

 experiments being made with each alkaloid for purposes of 

 contrast. 



It was found if the dose of aconitine, which is invariably 

 lethal per kilo, body weight, be represented by the unit, that 

 (in very general terms) diacetylaconitine would have ^V of the 

 toxicity of aconitine, benzaconine -;^, and aconine ttsVit- 

 There is, therefore, an enormous variation in toxicity amongst 

 these alkaloids. 



A few of the chief results obtained are here summarised. 



Aconitine in small doses slows the pulse, whilst larger 

 proportions not only accelerate but disturb the sequence of 

 ventricles upon auricles — an independent rhythm being pro- 

 duced at one stage of action. The central vaso-motor apparatus 

 is much more powerfully affected than the peripheral, great 

 respiratory acceleration precedes slowing, which, according to 

 the dose, may pass into failure. Sensory nerves are depressed 

 in function, whilst motor-nerve terminations and skeletal 

 muscle retain their activity, except when largely hyperlethal 

 doses have been used. 



Diacetylaconitine has less tendency to cause disturbance of 

 sequence between auricles and ventricles ; but, apart from vari- 

 ations in this and other minor points, its action is in the main 

 like that of aconitine. 



Benzaconine alters the cardiac rhythm, the pulse becoming 

 much slowed ; and at one phase of action the sequence of 

 ventricle fails to every second auricular beat. Entire suspension 

 of contraction may even occur, both auricles and ventricles, 

 followed by spontaneous resumption of systole. Respiration is 

 slowed from the first. 



Sensory nerves are but little affected, whilst motor-nerve 

 endings and, to a lesser degree, skeletal muscle show a reduced, 

 and curiously intermittent response to stimulation. 



