490 



♦ KNOWLEDGE . 



[Dec. 12, 1884. 



of the long-vanished race of Mexicans ; unless, indeed, the six 

 fingers and six toes were a mere sculptor's conventionalism, like the 

 protile eye in the Eg^-ptian bas-reliefs. Whether we shall ever have 

 a duodecimal system of notation until a sixth digit is developed on 

 the human hand and foot may well be questioned. — Ed.] 



" Let Knowledge grow from more to more." — Alfbbd Tenktsos. 



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A STEANGE FORM OF AFTERGLOW. 



[1530] — At 5.30 p.m. (local mean time) this evening, my atten- 

 tion was drawn to the abnormal appearance of the sea-horizon. 

 From the south to the west a lurid red f;lo\v extended at intervals 

 along the horizon for the complete quadrant. In three places the 

 glow was similar to that caused by largo conflagrations viewed from 

 a distance of some mOes. At the margins of these places what 

 seemed to be minute tongues of red flame flickered above the sea- 

 line. The sun set at 4.'19 p.m. (local mean time), and the evening 

 was dull and cloudy. Thermometer, 68° Fah. The barometer stood 

 at 30.35 in., and had been falling all the afternoon. At C.50 p.m. 

 the glow gradually faded and disappeared. We do not have much 

 twilight in these latitudes, and when I first observed the phenomenon 

 it was nearly dark. Hundredweight. 



Papho, Cyprus, Nov. 17, 1884. 



ECONOMY. 



[1531] — No one will dispute the proposition of " N." (letter 1506) 

 where he says, " No one can afford, or has any right, to be idle, and 

 were this generally acknowledged and acted upon, a certain stigma 

 would attach to those who lost their time doing nothing." If, in 

 addition to those " doing nothing," we consider what a number of 

 persons are employed in assisting their employers in '■ doing 

 nothing," it is well seen that with our present social system in the 

 matter of waste we make " assurance doubly sure." Take an 

 instance. A grant of £15,000 a year is expected shortly for an 

 individual who may one day occupy a position of doing nothing. 

 The amount of this grant reckoned as interest at 7 per cent, would 

 represent roughly a capital of £214,000, the consumption of which 

 in farming would require 21,000 acres, and absorb the energies of 

 nearly a thousand individuals working for the bare necessaries of 

 life. As facts should speak for themselves, no comment is required. 



C. F. N. 



DUODECIMAL NOTATION. 



[1532] — From Mexico comes the announcement of the discovery 

 of some curious ancient rock dwellings, cut out of a hill of gypsum, 

 upon the walls of whose rooms are numerous hieroglyphics and 

 representations of human beings cut in the rock. A strange featui-e 

 of these incised figures is that all the hands have six fingers and 

 the feet six toes. 



The reflection forced itself upon my mind as I read this : "How 

 changed would the arithmetic of this day be if our Asian fore- 

 fathers had had six fingers and toes, like these pictured ancient 

 Mexicans." It would involve the desired compromise between the 

 decimal and the duodecimal system. Our scale of notation would 

 then be duodenaiy, 12 digits instead of 10, and from this improved 

 decimal system would spring many practical advantages, among 

 the chief being that the decimal would then be divisible by 2, 3, 4, 

 and 6, instead of 2 and 5 only as present. 



This looked-for change may yet come with a higher civilisation ; 

 but we may, perhaps, expect the new universal language first, and 

 the realisation of a few other ideas of the scientific Utopian. 



R. CoupLAXD Thomas. 



[" There's a divinity," says Hamlet, "that shapes our ends;" 

 and whicb seems to have acted curiously in this respect in the case 



THE SENTIENT EYE THE ONLY COLOUR-BOX. 



[1533] — Your correspondent, " Cosmopolitan," still clings to the 

 venerable notion of the ewtervalify of colour; and until the fact be 

 accepted that colour, precise!}' as sound, has no external existence 

 whatever, but as mechanical, vibratory action, there can by no 

 possibility be a consistent arrangement of the phenomena of 

 light, nor any intelligible science of chromatics. The phrase, 

 " the light is within us," is not only a scriptural metaphor, but 

 a literal, scientific truth. Light and sound are the phenomena 

 alone of the sentient eye and of the sentient ear. Light is the 

 tcrtium quid of the contact of vibratory action with the inner 

 optic sense, just as sound is of mechanical atmospherical vibra- 

 tions with the auditory sense. That which is actually perceived 

 by the sensorium is, indeed, merely a property or change of 

 condition of our nerves. Why a simple mechanical vibration 

 should in the ear produce sound, and in the eye the sensation 

 of light, will in all probability never be ascertained. But the fact 

 shows us that there are phenomena which defy scientific analysis. 

 It is a fact of which, it has always appeared to me, metaphysicians 

 might have made much. The action of vibratory bodies on the 

 organ of hearing is entirely mechanical. If the action of the 

 mechanical cause on the ear be of continued duration, the sound 

 is also continued, and when caused by a rapid succession of 

 uniform impulses or vibrations, it produces a musical sound ; but 

 the unthinking attribute externality to the sound, and to the 

 note, just as they do to light and to colour. The undnlatory and 

 mechanical theory of light does not posit more than that the 

 different periodicities of the mechanical vibrations produce in us 

 different sensations cf light, different sensations of colour. If a 

 mechanical vibration, plus something else, were required to pro- 

 duce a sensation of colour, the undnlatory theory, as it stands, 

 would be insufficient. 



External agencies can give rise to no kind of sensation which 

 cannot also be produced by internal causes. Colour, light, and 

 darkness may be perceived independently of all external exciting 

 causes. The appearance of light and of luminous flashes may be 

 excited in the closed eyes independently of any external causes. 

 Everyone is aware how common it is to see bright colours while the 

 eyes are closed. These phenomena are very frequent in children 

 after waking from sleep. And even a person blind from infancy, 

 in consequence of opacity of the transparent media of the eye, 

 must have a perfect internal conception of light, colour, provided 

 the optic nerve be free from lesion.* Light and colours are innate 

 endowments of our nature, and merely require a stimulus to make 

 them manifest. By the corpuscular or emissive hypothesis, colours 

 might be supposed to be inherent in the corpuscules ; but we can- 

 not entertain the same notion with respect to the corpuscules of 

 the ether waves, for, if we did, the ether particles, chameleon-like, 

 would have to change their colour to adapt themselves to the dif- 

 ferent periodicities of their vibrations. This shows very forcibly 

 that light, colours, can by no possibility have externality other 

 than as vibratory action, and that the eye itself is the only colour- 

 box in nature. This admitted, the whole science of chromatics, as 

 popularly understood, has to he reconstructed. The fact, indeed, 

 is admitted by all thinkers on the Continent, and by a few thorough 

 scientists in England. Nevertheless, the science of chromatics 

 lingers on in the sloughs of error by the misleading of the New- 

 tonian nomenclature and false hypothesis. Primaries, secondaries, 

 &c., come of the thinking founded on the dead Newtonian hypo- 

 thesis, not on the undulatorv theory. W. Cave Thomas. 



53, Welbeck-street, Nov. 26, 1884. 



NO MATTER. 



[1534] — Respecting the letter by Mr. I. W. Alexander on 

 "Matter," (1518, p. 451) it is very confusing, if not irrational, to 

 say that matter never alters, and then to maintain that it can be 

 destroyed — i.e., reduced to nothing, to be re-created afresh out of 

 nothing ! The materialistic idea, as explained by Haeckel 

 (" Pedigree of Man," page 231), is; — " We must hold that atoms 

 are the smallest separate particles of masses, having an unalterable 

 nature, separated one from another by hypothetical ether. Everj- 

 atom has an inherent sum of force, and is, in this sense, gifted 



* There are many other facts which might be adduced to show 

 that the eye itself is the real seat cf light and colour. 



