to Henslow, who had undertaken the
care of them. In his letters he often expresses the greatest solicitude
lest the value of these specimens should be impaired by the removal of
the numbers corresponding to his manuscript lists. Science owes much
to Henslow's patient care of the collections sent to him by Darwin. The
latter wrote in Henslow's biography, "During the five years' voyage,
he regularly corresponded with me and guided my efforts; he received,
opened, and took care of all the specimens sent home in many large
boxes." ("Life of Henslow", by L. Jenyns (Blomefield), London, 1862,
page 53.)

Darwin's geological specimens are now very appropriately lodged for the
most part in the Sedgwick Museum, Cambridge, his original Catalogue with
subsequent annotations being preserved with them. From an examination of
these catalogues and specimens we are able to form a fair notion of
the work done by Darwin in his little cabin in the "Beagle", in the
intervals between his land journeys.

Besides writing up his notes, it is evident that he was able to
accomplish a considerable amount of study of his specimens, before they
were packed up for despatch to Henslow. Besides hand-magnifiers and
a microscope, Darwin had an equipment for blowpipe-analysis, a
contact-goniometer and magnet; and these were in constant use by him.
His small library of reference (now included in the Collection of books
placed by Mr F. Darwin in the Botany School at Cambridge ("Catalogue
of the Library of Charles Darwin now in the Botany School, Cambridge".
Compiled by H.W. Rutherford; with an introduction by Francis Darwin.
Cambridge, 1908.)) appears to have been admirably selected, and in all
probability contained (in addition to a good many works relating to
South America) a fair number of excellent books of reference. Among
those relating to mineralogy, he possessed the manuals of Phillips,
Alexander Brongniart, Beudant, von Kobell and Jameson: all the
"Cristallographie" of Brochant de Villers and, for blowpipe work, Dr
Children's translation of the book of Berzelius on the subject. In
addition to these, he had Henry's "Experimental Chemistry" and Ure's
"Dictionary" (of Chemistry). A work, he evidently often employed, was P.
Syme's book on "Werner's Nomenclature of Colours"; while, for Petrology,
he used Macculloch's "Geological Classification of Rocks". How
diligently and well he employed his instruments and books is shown by
the valuable observation