PREFACE. 



To disduss in a single volume the progress of sci- 

 ence in the nineteenth century has been no easy task, 

 and the author craves the reader's indulgence. It 

 must be remembered that the book does not pretend 

 to be a history of nineteenth century science; it 

 is designed simply as an introduction to many histo- 

 ries — some still unwritten. It is not a consecutive 

 story of the marvellous progress of knowledge which 

 the century witnessed ; it is simply a record of some 

 of the great scientific events. Many famous names 

 and many important discoveries have been left un- 

 mentioned, for any attempt at exhaustiveness would 

 have made a volume of this size a mere catalogue. On 

 the other hand, there has been a serious attempt to 

 discuss the great theme so as to give prominence to 

 the salient steps of progress. To have attempted this 

 in an easy-going mood would have been irreverent to 

 the past and insulting to the serious reader ; therefore 

 no apology is offered for the difficulty of some of the 

 pages, nor does it seem necessary to apologise for the 

 numerous quotations from expert authorities, — they 

 help to give personal reality to some of the pages, 

 and they were needed as acknowledgments of the 

 author's indebtedness. J. A. T. 



Univebsity of Aberdeen, September, 1902. 



