182 
advance or to retrograde, to go to the right hand or to the 
left, nor what place it shall take in the compound molecule. 
Whence, then, comes the free will which characterises this 
organised matter ? 
44. Certainly not from molecular combination ! 
45. I do not propose to myself the task of enabling my 
readers to keep pace with the progress of the science ; but 
having grown up with the atomic theory of Dalton, and from 
early youth followed with delight its further development, I 
find that I think chemically. T have constantly acted upon the 
certified details of chemical combinations with the same con- 
fidence that a traveller feels in consulting Bradshaw. He 
may complain of the bad type, or the arrangement of the 
contents, but the familiar book is his guide after all. 
46. I thus find myself in altogether a different country, and 
speaking a different language from others differently circum- 
stanced. It may seem very presumptuous to say that a writer 
who attempts to enlighten us in reference to “ the physical 
basis of life does not travel by the Bradshaw of science, and 
in fact proposes to lead us along the old high road. In proof 
of this I must refer to what I have already written, but the 
result of fuller study of his mind shows me that the difference 
between our views is much more fundamental {substantial) 
than I at first apprehended.* 
47. When, according to the Professor’s wish, we have “a 
scientific Sunday school in every parish,” f I hope the atomic 
theory will hold a prominent place in the instruction. No 
well-educated Sunday scholar would then think of listening 
to disquisitions on the Origin of things, such as we find in 
Huxley’s Lay Sermons, p. 128. 
48. At the risk of exacting an unreasonable amount of 
attention, I will now recall some of the elementary lessons in 
this science, and seek to show that we not only imagine, but 
know “that matter has a substance”; and that Newton’s 
views about the constitution of ultimate atoms are now 
as much the subject of proof as those about the falling of an 
apple. 
49. It was from the results of an examination of two gases 
(olefiant gas and marsh gas) that Dalton was first led to the 
conception of his theory. He ascertained that both gases con- 
sist of carbon and hydrogen only ; and set out the centesimal 
composition of each in the customary manner. But he observed 
* Compare Dr. Huxley’s Lay Sermons, p. 73, &c. Appendix C. 
t Ibid., p. 71. 
