is Carroll were identical.

The book in question, admirable as it is in many ways, has not
commanded a large sale. The nature of the subject would be against it,
as most students whose aim is to get as good a place as possible in
the class lists cannot afford the luxury of a separate work, and have
to be content with the few chapters devoted to "Determinants" in works
on Higher Algebra or the Theory of Equations, supplemented by
references to Mr. Dodgson's work which can be found in the College
libraries.

The general acceptance of the book would be rather restricted by the
employment of new words and symbols, which, as the author himself
felt, "are always a most unwelcome addition to a science already
burdened with an enormous vocabulary." But the work itself is largely
original, and its arrangement and style are, perhaps, as attractive as
the nature of the subject will allow. Such a book as this has little
interest for the general reader, yet, amongst the leisured few who are
able to read mathematics for their own sake, the treatise has found
warm admirers.

In the Summer Vacation of 1867 he went for a tour on the Continent,
accompanied by Dr. Liddon, whom I have already mentioned as having
been one of his most intimate friends at this time. During the whole
of this tour Mr. Dodgson kept a diary, more with the idea that it
would help him afterwards to remember what he had seen than with any
notion of publication. However, in later years it did occur to him
that others might be interested in his impressions and experiences,
though he never actually took any steps towards putting them before
the public. Perhaps he was wise, for a traveller's diary always
contains much information that can be obtained just as well from any
guide-book. In the extracts which I reproduce here, I hope that I have
not retained anything which comes under that category.

[Illustration: Dr. Liddon. _From a photograph by Lewis
Carroll_.]

_July 12th_.--The Sultan and I arrived in London almost
at the same time, but in different quarters--_my_ point
of entry being Paddington, and _his_ Charing Cross. I
must admit that the crowd was greatest at the latter place.

Mr. Dodgson and Dr. Liddon met at Dover, and passed the night at one
of the hotels there:--

_July 13th_.--We breakfasted, as agreed, at eight, or
at least we then sat down and nibbled bread and butter till
such time as the chops should be done, which