Page 6 - A HANDBOOK OF ORGANIC ANALYSIS QUALITATIVE AND QUANTITATIVE

INTRODUCTION
different from those in use for testing inorganic substances,
for by far the majority of organic compounds contain the
same elements. Groups, not elements, are the chief things
to be looked for, melting and boiling points have to be deter-
mined, and other physical data also give valuable informa-
tion to the chemist as to the nature of the compound under
examination.
It is by no means easy to arrange a general plan for testing
organic compounds so that one can say for certain what the
particular compound may be. But as organic chemistry is an
eminently practical science, there ought to be good practical
books dealing with the subject,--books where the descriptions
are concise, where the treatment of the subject is systematic
and not merely an enumeration of special tests for special
compounds, and where the student has to use his head as well
as the information supplied by the text-book. Mr. Clarke has
in this book recognised these requirements.
The most important novelty, however, in the book is to
be found in the Chapter ' Tables of Compounds.' In this
chapter Mr. Clarke has collected together the data that are
wanted by the ordinary student after he has determined as far I
as possible the nature of the organic compound he is analysing :
i.e. the nature of the radicles present, the elements present,
its melting and boiling point, and possibly its molecular
weight, Under ordinary conditions, after these data have
been obtained, a lengthy hunt through a dictionary or manual
of organic chemistry must be made to try to find what
particular substance agrees with the facts discovered. In the
'Tables of Organic Compounds' a complete list is given of all
i the more important compounds likely to be met with, together
with their properties, and thus much valuable time is gained
through the possibility of making a direct comparison of the
properties under investigation.
Mr. Clarke's book covers a very considerable amount of
ground, and gives practically all that an average student
should need. It will be of great assistance to anyone testing