TO 

 ALBEET B. PRESCOTT, M.D., LL.D. 



DIBECTOR OF THE OHEMIOAL LABOBATOBT IN THE mOVEBSITY OF HIOHIGAN, 

 THIS LITTLE WORK 



IS RESPECTFULLY DEDICATED 



AS A SLIGHT TOKEN OF THE HIGH ESTEEM IN WHICH 

 HE IS HELD BY HIS FOBMEB STUDENTS, 



THE AUTHOES. 



