But negative experiments prove nothing in a case like this, and the fact that most experimenters have failed where M.Blondlot and his pupils have succeeded may constitute a presumption, but cannot be regarded as a demonstrative argument.

Hence we must still wait; it is exceedingly possible that the illustrious physicist of Nancy may succeed in discovering objective actions of the N rays which shall be indisputable, and may thus establish on a firm basis a discovery worthy of those others which have made his name so justly celebrated.
According to M.Blondlot the N rays can be polarised, refracted, and dispersed, while they have wavelengths comprised within .0030 micron, and .0760 micron--that is to say, between an eighth and a fifth of that found for the extreme ultra-violet rays.

They might be, perhaps, simply rays of a very short period.

Their existence, stripped of the parasitical and somewhat singular properties sought to be attributed to them, would thus appear natural enough.

It would, moreover, be extremely important, and lead, no doubt, to most curious applications; it can be conceived, in fact, that such rays might serve to reveal what occurs in those portions of matter whose too minute dimensions escape microscopic examination on account of the phenomena of diffraction.
From whatever point of view we look at it, and whatever may be the fate of the discovery, the history of the N rays is particularly instructive, and must give food for reflection to those interested in questions of scientific methods.
Sec.6.THE ETHER AND GRAVITATION The striking success of the hypothesis of the ether in optics has, in our own days, strengthened the hope of being able to explain, by an analogous representation, the action of gravitation.
For a long time, philosophers who rejected the idea that ponderability is a primary and essential quality of all bodies have sought to reduce their weight to pressures exercised in a very subtle fluid.