REVIEWS. 
91 
not satisfy the unbelieving man of science it will very probably give the 
“ first shake ” to the opinions of those who have gone through life with 
their religious faith in one hand and their scientific belief in the other. But 
while we object to the space over which Mr. Gibson has taken us, we confess 
that we have been enlightened on many points in our journey together, and 
we thank him heartily for the extreme courtesy he has invariably exhibited. 
To show that the author is one who has clearly a scientific mind the reader 
need only refer to the following passage in which he alludes to a not infre- 
quent habit even among scientific men : — 
“ They talk sometimes of tracing things back to their nebulae, as though 
they were thus obtaining a comprehensive view of the entire history of 
creation. But supposing that the solar system did originate from a nebula, 
have they a right to assume this development to be coeval with the uni- 
verse ? We have good reason to think that stars are by no means of equal 
antiquity, and that our own sun is not one of the oldest. Further, that 
nebula out of which it sprung need not be thought the primitive state of 
matter. It might have been the result of some previous condition of things, 
say a collision of two great cosmical bodies and the vaporising of their 
masses.” 
There is another paragraph we should like to have inserted, as it shows 
the broad views of the author. It is that in which he takes to task Professor 
Birks for his assertion in the Scripture doctrine of creation that a if there 
never was a beginning of time the present moment could never have arrived.” 
There are many points in the argument which the present writer would 
wish to dwell on, but that space forbids. He therefore bids, he hopes, au 
revoir and not adieu to Mr. Gibson, and thinks he has with the worst 
materials at command made out a most excellent brief in the present case. 
E are sorry to be compelled once again to find fault with one of Messrs. 
King’s handbooks, the more so as we feel assured that that eminent 
firm has nothing whatever to do with the work under notice further than 
their labours as publishers, which are performed in a most thoroughly 
satisfactory manner. In its mere mechanical details the work is capitally 
done : no fault can be found with either the printing or illustrations of the 
book before us. But as a popular essay on a most interesting branch of 
optics, it is the most incomplete work that we have for a long time met 
with. The author seems to be devoid of that power of popularising his 
subject which is possessed in so marvellous a manner by our own Tyndall. 
And he has added to the difficulty by endeavouring to introduce elementary 
mathematics. Further, his descriptions are extremely incomplete in nearly 
every instance. Take, for example, what he has to say on the microscope as 
* u The Nature of Light, with a general account of Physical Optics.” 
By Dr. E. Lommel, Professor of Physics in the University at Erlangen. 
With 188 illustrations, &c. Henry S. King & Co. 1875. 
POPULAB OPTICS.* 
