PBOCEEDINGS OF SOCIETIES. 135 



The master mind of Newton was not fully alive to the importance 

 of the instrument ; for speaking of the extreme tenuity of the ultimate 

 molecules of bodies, he seems to have had but an inadequate idea of 

 their minuteness, and supposes that they might be seen through 

 microscopes magnifying some three or four thousand times (linear), 

 and in speculating upon the possible resolution of the colouring 

 matter of bodies — a speculation, as Herschel observes, " in the highest 

 tone of a refined philosophy, irrespective of its theoretic bearings," he 

 goes on to say : — " In these descriptions I have been the more particu- 

 lar, because it is not impossible but that microscopes may at length be 

 improved to the discovery of the particles of bodies on which their 

 colours depend, if they are not already in some measure arrived at 

 that degree of perfection. For if these instruments are, or can be, so 

 far improved as with sufficient distinctness to represent objects five or 

 six hundred times bigger than at a foot distance they appear to our 

 unaided vision, I should hope that we might be able to discover 

 some of the greatest of these corpuscles, and by one that would 

 magnify three or four thousand times, perhaps they might be all 



discovered except those which produce blackness However, 



it will add much to our satisfaction if those corpuscles can be dis- 

 covered with microscopes which, if we shall at length attain to, I fear 

 it will be the utmost improvement of this sense. For it seems impos- 

 sible to see the more secret and noble works of nature within the 

 corpuscles by reason of their transparency." 



Much of what must have appeared to be impossible to the earlier 

 workers with the microscope has been slowly and surely accomplished. 

 During the year 1801, histology became indirectly indebted to the 

 genius of a member of the medical profession, who, although not 

 himself a great discoverer, yet he so well understood how to arrange 

 existing materials, and bring them into harmony and close relation- 

 ship with physiology and medicine, that it soon acquired for itself an 

 independent existence. 



The future of histology was secured the moment Bichat gave to 

 the world his admirable treatise, ' Anatomie Generale.' 



This work may certainly be said to be the first scientific monograph 

 on histological physiology ; for in it the tissues are not only treated 

 of fully and logically from a morphological point of view, but their 

 physiological functions and morbid conditions are discussed somewhat 

 in detail. About the time this book made its appearance, many im- 

 provements were effected in the optical part of the microscope — a 

 circumstance which gave an impetus to the growing desire for a more 

 careful and systematic study of natural history — so that more 

 appears to have been accomplished in a few years than bad previously 

 been effected in two hundred. Discovery quickly followed discovery, 

 and in 1823 the first attempt to furnish the instrument with an 

 achromatic objective proved successful both in France and in this 

 country simultaneously. In the following year, 1824, Mr. Joseph 

 Lister, the father of Professor Lister, of Edinburgh, fully accom- 

 plished what he had long laboured to produce, namely, a perfect 

 combination of achromatic lenses, together with the mode of obtaining 



