HISTORICAL INVESTIGATION. 19 



scopes formed the beginning of a new epoch in histological pur- 

 suits. Since that period, the confusion and opposition which 

 formerly existed among observers have diminished, and at 

 present only those differences remain which are incident to the 

 pursuit of any other branch of scientific study. 



In our own times, the Germans seem to have taken the lead 

 in histological observations; and the reputation of the well- 

 known names of Ehrenberg, Miiller, Schwann, Schulz, Wagner, 

 Weber, and Valentin, principally depends on the discoveries 

 they have made by means of the microscope. 



In England, the names of Carpenter, Todd, Bowman, Owen, 

 Cooper, Busk, Quekett, Bowerbank, and others, are connected 

 with microscopic research. 



In our own country, a spirit of emulation seems excited 

 which promises great advantage. Professor Bailey of West 

 Point, and our townsmen, Drs. Leidy and Goddard, may be 

 mentioned among others who have contributed to this result. 

 The recent lectures of Dr. Goadby (late minute dissector to 

 the Royal College of Surgeons, England), on microscopic 

 science have done much to increase a desire on the part of 

 medical students and others to become practically acquainted 

 with this subject. His lectures to the students of the Phila- 

 delphia College of Medicine, and at other places, were well 

 attended ; as likewise were his private classes. Of his valu- 

 able suggestions I have frequently availed myself. 



The advantage of a practical acquaintance with the micro- 

 scope by medical men may be easily seen, and is readily 

 acknowledged. Dr. Bennet, of Edinburgh, to whom I am 

 indebted for much of the histological part of this introduction, 

 says " I have lately had many opportunities of satisfying 

 myself that death may be occasioned by structural changes in 

 the brain which are altogether imperceptible to ordinary vision 

 and which have escaped the careful scrutiny of the first morbid 



