i88i.] 
Correspondence. 
365 
and support, than to controvert his arguments. I thought, and 
still think, that we are both on the same side in the contest be- 
tween Theistic and Atheistic Philosophy, which so sadly divides 
modern scientists. I have no doubt, however, that he will pardon 
my making a few remarks upon certain observations in his second 
article, touching my letter. 
1. Allow me to say that I did not suppose that he aimed at 
originality , seeing that the subject was one that scarcely admitted 
of it. 
2. I fully agree with his severe, but well-merited remarks upon 
the wild and often absurd theories propounded by some (so-called) 
philosophers, both ancient and modern. 
3. Haeckel on Spontaneity. I am quite aware of the definition 
Prof. H. gives of spontaneous or equivocal generation, as well as 
the ordinary sense of spontaneous , as applied to the feelings or‘ 
actions of men or animals, when not controlled or influenced by 
any extraneous will. But I must still maintain, that to talk of 
that which has yet no existence as exerting will ( sponte ), to give 
itself existence, is absolutely contradictory. I do not indeed 
imagine that anything we can say (hard or not) would weigh one 
feather with these self-sufficient Monists ; but that is no reason 
why we should abstain from exposing their fallacies, to the best 
of our ability, for the benefit of “ casual readers and half-thinking 
men.” 
4. The Ether. We apparently differ slightly as to the nature of 
this medium, which must needs be to a great extent conjectural : 
Mr. B. considering it (p. 82) as “ a gaseous substance,” from the 
solidification of which “ solid substances ” (not stratifications, as 
first written) have arisen ; or (p. 272) the “ one primordial sub- 
stance from the modification and differentiation of which all 
other forms of matter have arisen ” ; while I prefer to regard it as 
a permanent form of matter, but one sui generis. Let the two 
notions go for what they are worth. But looking to Mr. B.’s 
original words and their explanation, I cannot see that I was 
guilty of “ raising a phantom assumption.” I fully agree, how- 
ever, that the Ether is “ a subtle something which permeates the 
universe, and which proceeds direCt from the will of the Creator, 
in which all things exist.” 
One word as to the epithet luminiferous (so wofully mangled 
in the printing). It was doubtless conferred upon the ether, 
because, as its existence was first revealed by light , so it brings , 
or is the vehicle of, light. Paradoxical as it may appear to ordinary 
apprehension, neither light nor heat, as such, have an objective 
existence at all. They are only rates of vibratory motion, trans- 
lated into subjective sensations in the nervous system by the 
correlative powers of the living mind. 
Mr. Billing (p. 273) implies that I consider the ether to be the 
source of light (a term I did not use), and objects that, if it were 
so, the higher we get in the air “ the brighter should be the 
aspect,” while balloonists find it both darker and colder. To this 
