creatures ; and that even in niglit-time the surface of the earth is vibrating, far too 

 feebly, indeed, to excite vision in man, but sufficient for a vastly wide range of animal 

 life, to whom eyes have been given extremely susceptible to the ethereal vibrations. 

 The great Creator has furnished each class of his creatures with visual organs fitted 

 for their peculiar sphere of action ; and man, made for the day and the sunshine, has 

 eves whose rano-e of discernment is limited to the diurnal phenomena. His organ of 

 sight is adapted for a certain degree of light, more or less than which tends equally to 

 blindness. He is not more baffled by the shadows of night than by a superabundance 

 of the illuminating rays. Light itself may become darkness. The eagle gazes undaz- 

 zled on the orb of day ; but to us, the sun in its noontide splendor is an invisible spot 

 in the sky ; and " dark from excessive bright," is a phrase not more poetic than true. 

 Since, then, our range of vision is thus limited, let us beware of dogmatising as if light 

 were a word of absolute instead of relative significance ; and although we may not be 

 able to see what Reichenbach's sensitives saw, still less to walk by the feeble rays 

 which suffice for the lower creation, let us confess that the auroral and zodiacal lights, 

 as well as all sound reasoning, show that Earth has a light of her own, by which it is 

 as seemly that some orders of creatures should walk, as we, children of light and of 

 the day, by the nobler radiance of the sun. 



It is known to men of science that every part of nature, even the hardest and most 

 solid, is in a state of molecular motion, so subtle, as in most cases to defy occular 

 scrutiny, yet indubitably revealing itself in its eftects.'* It is only when tho^e vibra- 

 tions grow strong and frequent that they become perceptible to our senses ; and then 

 they do so in the fonn of those ether-born twins, heat and light. Let us examine the 

 spectrum, and see how this vibratory motion exhibits itself in the production of color. 

 To the ordinary eye, the spectrum, produced by refracting or breaking up the symmetry 

 of the solar beam, is merely a series of hues, beginning with red, brightening into 

 yellow, and then fading away through violet into darkness. But if you examine it 

 scientifically, you will find that those bright hues are produced by a series of tremors 

 or vibrations of the broken ethereal ray ; the strongest and slowest of which vibratoiy 

 rays are least refracted, and form the red, and the feeblest and most rapid are most 

 refracted and form the violet. But the whole of the broken rays are not represented 

 by the colors which meet the eye in the spectrum ; for at either extremity, where the 

 red and violet fade out of sight, a succession of rays spread out, invisible to our eyes, 

 but which might be to some extent discernable had we the night-eyes of some of the 

 lower animals. The invisible rays at the red end are the strongest and rarest in the 

 spectrum, only showing themselves by giving out heat, and an electricity which is 

 positive; those at the violet end are the feeblest and densest, — only showing them- 

 selves by their chemical or actinic properties, and by an electricity which is negative. 

 Thus the spectrum exhibits a complex phenomenon. Firstly, we have a series of rays 

 steadily increasing in rapidity and weakening in force of vibration, from one end to the 



♦"Nothing can be more certain," says Mrs. Somkrville, "than that the minute particles of matter are constantly 

 in motioQ, from the action of heat, mutual attraction and electricity. Pri.smatic crystals of salts of zinc are changed 

 in a tew seconds into crystals of a totally Uifferent form by the heat of Uie sun ; — casts of shells are found in rocks, 

 from which the animal matter has been removed, and its place suiiplied by mineral : — and the excavations made in 

 rocks diminish sensibly in size, in a short time, if Uie rock be soft, and in a longer time when it is hard : cireum- 

 stnncca which shew an intestine motion of the particles, not only in their relative positions, but in space, which there 

 is every reason to believe is owing to electricity, — a power which, if not tjie sole agent, must at least have co-oper- 

 ated cssentiall/ in the formation and flUing of mineral veins." — Physical Geography, I, Chapt. xv. p. 288-9. 



