PREFACE, 



The present memoir is the outcome of labor, which has occupied during many 

 years all the hours that could be spared from pressing professional engagements. 

 Like other works, which have grown up rather than been fully conceived of in 

 the beginning, it has taken a final form somewhat different from that which 

 originally shaped itself in the author's mind, having been especially modified by 

 the hand of death laid upon those who were to have been co-workers to the end. 



It was intended that the memoir should be a complete discussion of the subject 

 on which it treats ; including in its scope the chemistry of fever and tlie relation 

 of the febrile state to ingestion and elimination. I am not a practical chemist, 

 but Dr. Horace Hare was to have had charge of the chemical portion of tlie 

 research, which would have been published under our joint names. After some 

 months spent in devising, preparing, and testing apparatus. Dr. Hare was over- 

 taken by the malady which ultimately caused his death. Tiiis deranged all our 

 plans, and resulted in my continuing alone the share of work originally allotted 

 to me. 



It is, perhaps, allowable for me in this place to pay a brief tribute to the memory 

 of one who took an active part in preparing tlie groundwork of the present research. 

 Fitted by natural endowments and by careful scientific training both in this 

 country and abroad, Dr. Horace Hare, had he lived, would have proved himself 

 worthy to bear the name of his grandfather, Prof. Hare, who so long gave lustre 

 to the chemical chair in the Medical Department of the University of Pennsyl- 

 vania, By industry and originality he was fitted to shine as an investigator; by his 

 remarkable personal winsomeness and his gifts as a public lecturer he was destined 

 to have become a great teacher of his favorite science — had not death ended all. To 

 him the author owes, not only memories of many hours spent most pleasantly and 

 instructively, but gratitude for suggestions, for manifold aid, given at a time when 

 the task, now completed, seemed hopeless in its complexity and magnitude. 



I also desire to acknowledge great personal indebtedness to Dr. B. F. Lauten- 

 bach, whose young life was put out by tlie same fatal disease that ended the career 

 of Dr. Hare. First as a [mini and afterwards as an assistant, Dr. Lautenbach was 



