England finally suggested its inclusion in the family and the name water-
soluble "C." As soon as its presence was admitted and its properties
roughly determined the way was opened to development of the antiscorbutic
vitamine hypothesis and that has now proceeded as rapidly as in the other
fields. During the past year many contributions have been made in this
field. Sherman, La Mer, and Campbell have recently published results that
have taught us much about the measurement of this new member and its
manipulation in experimental study of scurvy.

The year 1920, then, has brought us to a recognition of at least three
members of the family. Still more recently another deficiency disease has
been under investigation and Hess has found in cod-liver oil a remedy for
rickets that he cannot believe owes its efficiency to the "A" type.
Mellanby of England believes the "A" vitamine is the preventive factor in
this disease but Hess's results at least suggest the possibility that the
antirachitic vitamine may be separate and distinct from any of those yet
named, possibly vitamine "D?" Others are beginning to doubt the identity
of the rat growth promoter and the beri-beri curing complexes and feel
that the "B" itself may be the name of a group instead of a single entity.
All of these features make one feel uncertain to say the least, as to the
limits of this vitamine family or of the future possibilities but enough
has been given to indicate the historical development to date and we can
now turn to more special features of the subject and their bearing on
every day affairs.



CHAPTER II