nature, as were Malpighi, Mariotte or Hales; compared with
those great thinkers he was only a compiler, and a somewhat
uncritical one. But he was not a dilettante in science, like
Bonnet; he made the vegetable world the subject of serious
and diligent study, and he endeavoured to turn the results
of that study to practical account. Long familiarity with plants
gave him a kind of instinct for the truth in dealing with them,
as is shown in his observations and experiments, many of
which are still instructive; but he had neither that faculty
of combination which can alone bring a meaning out of
experiments and observations in physiological investigations,
nor the power to distinguish between matters of fundamental
and secondary importance. So thinks also his biographer
Du Petit-Thonars.
The merits and the faults here mentioned are combined in an especial degree in Du Hamel's most famous work, 'Physique des arbres,' which appeared in two volumes in 1758 and is a text-book of vegetable anatomy and physiology with numerous plates. His remarks on the nutrition of plants and the movement of the sap are a lengthy compilation chiefly from Malpighi, Mariotte and Hales, though he has not succeeded in appropriating .exactly that which is theoretically important or adopting the most commanding points of view. He introduces the results of his own experiments into his account, and these are often instructive in themselves, but are never made use of to establish a definite view with respect to the connection between the processes of nutrition. He hits upon the right view only when he is dealing with plain and obvious matters; for instance, he restores the vessels of the wood to their old rights, and concludes from experiments, as had been already done in the 17th century, that an elaborated sap moves in the reverse direction in the rind;
on presenting to it an essay on a disease then raging in the saffron-plantations, and caused by the growth of a fungus ('Biographic Universelle').
