Miss Johnson agrees with this, and in fact goes so far as to say: "If these hands had been completely invisible to some person with normal sight looking directly at them in a good light, we should then have good evidence that they were hallucinatory."[28] To this I cannot agree. I find myself completely differing from Miss Johnson in my interpretation of such an incident as this. For, while hallucination is one possible theory to account for the phenomena, another equally plausible theory is that the hands were in fact objective and real, but were only perceptible to various individuals in varying degrees. This aspect of the problem is hardly touched upon by Count Solovovo, but is discussed at some length by Miss Johnson. In this connection she says: "Here [in the hand, i.e.] is a kind of matter which is not only temporary in character--a fact in itself extraordinary enough--but exhibits another quite unprecedented characteristic in the arbitrary selectiveness of its effects on other matter. In order to be visible at all, it must reflect light. How does it manage to reflect light that affects the retina of one person and not the retina of another? We may reply that the difference must lie in the retinae, one being more sensitive than the other. But we do not find the same difference of sensitivity in regard to the light reflected from ordinary objects. It seems to follow then that the light reflected from the spirit-hand is a peculiar kind of light, lying outside the limits of the ordinary visible spectrum. But in that case, why is not the person with the more sensitive retina affected by it? For of course all ordinary objects are constantly giving off radiations outside the limits of the visible spectrum; but our supposed sensitive apparently does not perceive them."[29] First, as to the matters of fact. Where is the evidence that those with the most sensitive retinae were not the very ones who perceived, most perfectly, the spirit-hand? Were a series of experiments conducted to show which of the onlookers possessed the most sensitive eyes? If so, where are these experiments recorded? It is quite possible that the body is constantly giving off a kind of _aura_--perceptible to some, invisible to others; and the fact that some do not see it is no proof that it is not there. If the experiments of Reichenbach and others go for anything, indeed, there is very good evidence that such emanations do take place--and I venture to think (however rank heresy this may appear) that these experiments have never been completely refuted, and the results obtained shown to be traceable _in toto_ to suggestion. The eyes of certain individuals might be attuned to receive vibrations or impressions quite imperceptible to others, no matter how sensitive their retinae to normal perceptions or sensations.