THE PRESIDENT'S ADDRESS. 101 



I have selected these aphorisms from a larger number which have 

 occurred to me from time to time in my reading,* because they seemed 

 the most easily applicable to the solution of my question, as well as 

 the most terse. But I must admit that they are by no means ex- 

 haustive, and that the subject merits, and indeed admits of a more, 

 extensive treatment. But then this Address would have been pro- 

 longed far beyond its proper limits, and would possibly have taxed 

 your patience unduly. Moreover I ought, perhaps, to have con- 

 sidered these axioms seriatim in reference to their help in assign- 

 ing its due place to Microscopy ; but then, again, this Address would 

 certainly have swollen into a volume. I have therefore confined 

 myself to a few illustrations (or applications), leaving the rest to be 

 filled up by my hearers at their leisure, if the subject really interest 

 them. There can be but little doubt that most of, if not all, the 

 sciences began their existence as arts. Thus one of the best of 

 modern treatises on surgery has been entitled by its author " The 

 Science and Art of Surgery," by John Eric Erichsen. But surely 

 the words " Science and Art " should have been transposed, since 

 the word " Surgery " means hand-work, and thus was at first an 

 Art or Handicraft, whatever has been its subsequent developement 

 into a science. It may serve as an evidence of the light in which 

 microscopy was regarded by the late Mrs. Somerville, when we find 

 that her very last scientific treatise was thus entitled " On Molecular 

 and Microscopic Science.'''' Clearly, then, microscopy seemed some- 

 thing more than an art to such a master-mind as hers. The Art of 

 Microscopy began, I take leave to assert, with the discovery of 

 Glass, so that its birth is hidden in the midst of ages. Layard 

 found a lens amongst the ruins of Nineveh. I am of opinion that 

 it was scarcely possible to manipulate glass, which is essentially, even 

 in its oldest forms, a transparent or translucent body, without recog- 

 nising its refractive powers. f The science of Microscopy certainly 



* J. S. Mill, Dr. J. Brown, Belmholtz, and others. 



f We may here notice some facts connected with glass, which shew that 

 the ancients were on the verge of making one or two very important dis- 

 coveries in physical science. They were acquainted with the power of 

 transparent spherical bodies to produce heal by the transmission of light, 

 though not with the manner in which that heat was generated bj the con- 

 centration of the solar rays. Pliny mentions the fact tbat hoHow glass balls 

 filled with water would, when held opposite to tbe sun, "grow hot enough 

 to burn any cloth they touched;" but the turn of his expression evidently 

 leads to the conclusion that he believed the heat to become accumulated in 

 the glass itself, not merely to be transmitted through it. Seneca speaks of 

 similar glass balls vihich magnified minute objects to the view. Kay, he had 



