122 



NA TURE 



[December 9, 1897 



something akin to the third law of motion, though that is 

 not in the least understood by them ; and by " Equalisa- 

 tion " is intended something like the second law of 

 thermodynamics, viz. that unless a difference of state 

 exists between two bodies, there is no activity or 

 tendency to activity. 



Thus it may be admitted that the customary teachings 

 of science have not been wholly thrown away upon 

 Messrs. Singer and Berens ; they have acquired some 

 rudimentary notions from their perusal of popular exposi- 

 tions of science, but the amount of vagueness and in- 

 accuracy with which they have contrived to shroud those 

 notions is almost incredible except to those who take the 

 trouble to read their book. 



In the first place, they are careful to confuse their 

 terminology, as the following explanatory notes testify : — 



" We use the terms force and energy synonymously, 

 and in the sense of power or strength, and shall use 

 either of these indiscriminately as the one or the other 

 may happen to be most convenient (p. 49). 



"To us 'heat' means simply temperature." Work 

 can be got from a body by either heating or cooling it, 

 and it is the degree of difference of temperature that is 

 important in connection with the mechanical equivalent 

 of heat, not heat/^rj'^ (pp. 86, 88). 



" Pressure is ' work,' and so is motion" (p. 106). 



"'Force' and 'mass' (or 'weight' and 'mass') are 

 synonymous terms ; two different names for one and the 

 same thing." And yet the proportionality of weight and 

 mass or of gravitation force and mass is put forth as a 

 real fact of the Newtonian theory (p. 349). 



In the second place, they ignore in detail the laws 

 which they admit in general. For instance, on p. "j"] 

 occurs the following illustration : — 



" Two bodies attracting each other, the one with a 

 force of 100 and the other with a force of 10, the stronger 

 body would be pulled one-tenth and the lesser nine- 

 tenths out of their respective positions." 



And many other instances might be given of their 

 entire misapprehension of Newton's third law. 



There are many singular instances of what appears to 

 be malevolent criticism, statements of the beliefs or 

 usages of orthodox science which are utterly destitute of 

 basis in fact. The following may serve as illustrations : — 



" Confining our attention to what are called the 

 physical sciences, we still find the greatest possible 

 differences in both language and conception. We have 

 hydraulics and hydrostatics, mechanics, dynamics and 

 pneumatics, electricity and magnetism, light, sound, and 

 heat, and so forth ; each separate branch of knowledge 

 having its own distinctive theory and peculiar termin- 

 ology not applicable to the others. It is like the con- 

 fusion at the Tower of Babel. The workers in the 

 different fields of knowledge cannot understand each 

 other, therefore cannot commune with each other for the 

 purpose of seeing whether the conclusions deduced from 

 one group of facts agree with the conclusions derived in 

 other fields of inquiry." 



"The close relation of the different phenomena 

 embraced under electricity, magnetism, and galvanism is 

 now well known, yet are they still treated as separate 

 and distinct sciences." 



• On p. 39 it is asserted that Newton's pendulum ex- 

 periments, whereby he proved that inertia and weight 

 were proportional, were proofs of nothing whatever, 

 being only equivalent to using first one balance and 

 NO. 1467. VOL. 57] 



then another. And on p. 40 it is said that when Newton 

 found that pendulum bobs composed of two different 

 materials swung together if their centres of oscillation 

 agreed, he must have adjusted their centres of oscillation 

 experimentally by means of equal times of swing. 



In other words, he was either a fool or a knave ; the 

 full-blown paradoxer would not have shrunk from the 

 appropriate epithets. But our authors are more polite ; 

 they are good enough to say, " Our quarrel is not with 

 Sir Isaac Newton, but with human frailty " ! 



"The fixing of the absolute zero at -273" C. is based 

 on the theory that at that temperature a body would 

 practically be annihilated — a conclusion which in a 

 previous chapter we have shown to be unwarranted by 

 the facts " I 



There is more about this absolute zero of temperature, 

 which is evidently a bugbear, and is considered as non- 

 sensical as absolute position or absolute truth ; in fact, on 

 the subject of thermodynamics generally the authors are 

 naturally afflicted with wholesale ignorance, which they 

 believe to be scepticism. " The action of the steam 

 engine is generally attributed to heat," they say on p. 84, 

 " and calculations are based as to the quantity of work 

 to be got out of a heat engine on the supposed mechan- 

 ical equivalent of heat," and they proceed to point out the 

 errors in this view. It appears that " the true cause of 

 the motion of the piston is a disturbed equilibrium, and 

 consequent tendency to equalisation." " Heat is no more 

 an entity than acidity or hardness or depth of colour." 

 In fact the whole doctrine of energy is absurd. 



"The whole doctrine of 'energy,' with all its astound- 

 ing and contradictory corrollaries, has not been deduced 

 from any facts at all, but is begotten of those conceptions 

 which have come down to us in unbroken succession 

 from our primitive and ignorant ancestors. The facts 

 have merely been distorted in order to make them fit 

 into the mould of the prejudiced human mind." 



After this they proceed to " deal with the error which 

 has given rise to the doctrine of the dissipation of 

 energy." " When estimating the efficiency or power of 

 doing work of a body we do not measure i\\& force which is 

 just necessary io arrest its motion [as we ought to do, is 

 implied], but that which actually causes it to move a 

 certain distance ; in which case there is bound to be a 

 discrepancy, an apparent loss." 



Joule's experiments involved also a fundamental 

 error, "owing to his assumption that a certain weight 

 descending a certain height in a certain time is the 

 measure of its mechanical power." 



" Where he committed the error was that he assumed 

 the whole power of the descending weight to have been 

 expended in driving his mechanism, [but] to produce 

 motion in the mechanism the weight had to be greater 

 than the resistance of the latter, . . . The power of the 

 weight was greater than the mechanical effect in his 

 paddles, and hence greater than the corresponding 

 thermal effect. But by how much greater Joule never 

 thought of determining." 



No, alas, he believed practically as well as theoretically 

 that action and reaction were equal. 



" Instead of estimating the ' heat ' produced by friction, 

 and then dividing the assumed mechanical power by the 

 number of heat units— as Joule did —he might have esti- 

 mated the mechanical effect produced by 'heat,' and 



