Ragnarok : the age of fire and gravel

WHAT IS A COMET? v7

The very fact that these waves of motion run through the tail of the comet, and that it is capable of expanding and contracting on an immense scale, is conclusive proof that it is composed of small, adjustable particles. The writer from whom I have already quoted, speaking of the extraordinary comet of 1843, says:

“ As the comet moves past the great luminary, it sweeps round its tail as a sword may be conceived to be held out at arm’s-length, and then waved round the head, from one side to the opposite. But a sword with a blade one hundred and fifty millions of miles long must be a somewhat awkward weapon to brandish round after this fashion. Its point would have to sweep through a curve stretching out more than six hundred millions of miles; and, even with an allowance of two hours for the accomplishment of the movement, the flash of the weapon would be of such terrific velocity that it is not an easy task to conceive how any blade of connected material substance could bear the strain of the stroke. Even with a blade that possessed the coherence and tenacity of iron or steel, the case would be one that it would be difficult for molecular cohesion to deal with. But that difficulty is almost infinitely increased when it is a substance of much lower cohesive tenacity than either iron or steel that has to be subjected to the strain.

“There would be, at least, some mitigation of this difficulty if it were lawful to assume that the substance which is subjected to this strain was not amenable to the laws of ponderable existence ; if there were room for the notion that comets and their tails, which have to be brandished in such a stupendous fashion, were sky-spectres, immaterial phantoms, unreal visions of that negative shadow-kmd which has been alluded to. This, however, unfortunately, is not a permissible alternative in the circumstances of the case. The great underlying and indispensable fact that the comet comes rushing up toward the sun out of space, and then shoots round that great center of attraction by the force of its own acquired and ever-increasing impetuosity ; the fact that it is obedient