8 



THE CELL AND PROTOPLASM 



many discoveries of a fundamental nature. 

 Unfortunately the very abundance of his 

 experiments precluded a proper publica- 

 tion of them. His experiments and dis- 

 cussions at the meetings of the Royal So- 

 ciety kept it alive and active during its 

 formative period, and "it is scarcely an 

 exaggeration to say that he was, histor- 

 ically, the Creator of the Royal Society" 

 (Robinson 1935). 



In 1665, Hooke published a remarkable 

 book entitled " Micrographia or Some 

 Physiological Descriptions of Minute Bod- 

 ies made by Magnifying Glasses." Using 

 a compound microscope of excellent form 

 which he had made himself, he described 

 and figured sixty different types of micro- 

 scopical objects. The section of the book of 

 especial interest to us is entitled "Observ. 

 XVIII. Of the Schematisme or Texture 

 of Cork, and of the Cells and Pores of some 

 other such frothy Bodies," which begins 

 thus : " I took a good clear piece of cork 

 and with a penknife sharpened as keen as a 

 razor, I cut a piece of it off, and thereby 

 left the surface of it exceedingly smooth, 

 then examining it very diligently with a 

 Microscope, methought I could perceive it 

 to appear a little porous." Further study 

 of thin sections showed that it was "all 

 perforated and porous, much like a honey- 

 combe ... in that these pores, or cells, 

 were not very deep, but consisted of a great 

 many little boxes, separated out of one con- 

 tinued long pore by certain diaphragms." 

 That he realized the importance of this 

 observation is shown by the following: "I 

 no sooner discerned these (which were in- 

 deed the first microscopical pores I ever 

 saw, and perhaps, that were ever seen, for 

 I had not met with any writer or person 

 that had made any mention of them before 

 this) but methought I had with the discov- 

 ery of them presently hinted to me the true 

 and intelligible reason of all the phenom- 

 ena of cork" {i.e., its lightness, impervious- 

 ness and compressibility). Of course he 

 knew nothing of the way in which these 

 cells were formed nor of the substance 

 which had filled them in life, though he 

 says of the cells of other plants, "In sev- 



eral of those vegetables, whilst green, I 

 have with my microscope plainly enough 

 discovered these cells or pores filled with 

 juices." Hooke counted three score of 

 these cells of cork placed end ways in the 

 eighteenth part of an inch and he calcu- 

 lated that there were 1,166,400 in a square 

 inch, or "above 12 hundred million in a 

 cubic inch, a thing almost incredible." 

 He showed that this cellular structure was 

 not peculiar to cork for he subsequently 

 found it in many other plant tissues. 



Nehemiah Grew (1628-1711), English 

 botanist and Secretary of the Royal Society 

 (1677-1679), published numerous treatises 

 on vegetable structures and functions. In 

 his "Anatomy of Plants," published in 

 1672, he showed that the parenchyma of 

 plants is composed of vesicles or closed 

 spaces in a homogeneous ground mass. In 

 1675 and again in 1679, Marcello Malpighi 

 (1628-1694), an Italian anatomist, physi- 

 ologist and physician, published two folio 

 volumes which justify his being called 

 "creator of scientific botany." He distin- 

 guished different plant tissues and called the 

 cells of the parenchyma ' ' utricles. ' ' His fig- 

 ures also indicated that even plant vessels 

 are composed of series of utricles joined 

 end to end. 



The Dutch microscopist, Antony van 

 Leeuwenhoek (1632-1723), was one of the 

 most colorful and indefatigable students of 

 microscopical objects during the late 17th 

 and early 18th centuries. He used only 

 simple lenses and it is amazing what he 

 could see with them. In 1673 he sent his 

 first paper to the Royal Society, and from 

 that year until his death in 1723 the Royal 

 Society received 375 letters and papers 

 from him, while 27 more were sent to the 

 French Academy of Sciences. In addition 

 to his studies on numerous protozoa and 

 protophyta and on the microscopic anat- 

 omy of plants and animals, he discovered 

 bacteria and spermatozoa and with his sim- 

 ple lenses he thought he saw in the human 

 spermatozoon the homunculus, or little 

 man, postulated by the preformationists. 



During the next hundred j^ears several 

 botanists and anatomists saw and figured 

 the utricles or vesicles in plants and ani- 



