56 BIOLOGY AND ITS MAKERS 
Newton, and also the use of a spring for regulating watches 
before Huygens, etc. He gave his attention to microscopic 
study fora time and then dropped it; vet, although we can not 
accord to him a prominent place in the history of biology, 
he must receive mention as a pioneer worker with the micro- 
scope. His book gave a powerful stimulus to microscopy in 
England, and, partly through its influence, labor in this field 
was carried on more systematically by his fellow-countryman 
Nehemiah Grew. 
The form of the microscope used by Hooke is known 
through a picture and a description which he gives of it 
in his Micrographia. Fig. 12 isa copy of the illustration. 
His was a compound microscope consisting of a combination 
of lenses attached to a tube, one set near the eve of the ob- 
server and the other near the object to be examined. When 
we come to describe the microscopes of Leeuwenhoek, with 
which so much good work was accomplished, we shall see 
that they stand in marked contrast, on account of their sim- 
plicity, to the somewhat elaborate instrument of Hocke. 
Grew (1628-1711) devoted long and continuous labor to 
microscopic observation, and, although he was less versatile 
and brilliant than Hooke, his patient investigations give him 
just claim to a higher place in the history of natural science. 
Grew applied the microscope especially to the structure of 
plants, and his books entitled Idea of a Philosophical His- 
lory of Plants (1673) and Anatomy of Vegetables (1682) 
helped to lay the foundations of vegetable histology. When 
we come to consider the work of Malpighi, we shall see that 
he also produced a work upon the microscopic structure of 
plants which, although not more exact and painstaking than 
Grew’s, showed deeper comprehension. He is the co- 
founder with Grew of the science of the microscopic anatomy 
of plants. : 
Tt is not necessary to dwell long upon the work of either 
