180 TRANSACTIONS OF THE [MARCH 15, 



euiiliony in sucli words ns pentamethyldiamidothiodiplien^'l- 

 nniindiiodomethj'late (a substance begotten and baptized by Dr. 

 Albert Maasen). 



Those whose chemical education consisted in attendance on a 

 course of lectures illustrated by experiments performed in their 

 presence, interspersed with occasional recitations from a prosaic 

 text-book which taxed tiie memory in true Chinese fashion, may 

 be pardoned for retaining very hazy impressions of the true char- 

 acter of the science. On the other hand, many thinking and 

 reading persons recognize the magnitude of the scope and opera- 

 tions of chemistry, and have some appreciation of its benefits to 

 mankind. 



(2.) 'JMie fields of chemistry exploi-ed by zealous investigators 

 are prodigious in extent and diversity; in its various sections, 

 analytical, agricultural, pharmaceutical, physiological, and tech- 

 nological, it yields fruit of infinite value to the human race, and, 

 co-operating with other sciences, produces results which promote 

 civilization in the highest degree. So rapidly are new methods of 

 cultivation applied to these fields, so numerous and active are the 

 workmen engaged in tilling them that the harvest is too abundant 

 for mental storage, and those who survey the operations at a dis- 

 tance are quite unable to apprehend the products. This ina- 

 bility to follow the advances made by chemical science is felt not 

 alone by tliose whose imperfect and non-technical training has 

 illy fitted them for the task; even the specialist stands aghast 

 at the prosi)ect, and abandoning attemjjts to apprehend the pro- 

 gress made in all departments, confines iiis reading and research 

 to a limited number. 



The twelve principal Chemical Societies of the world have an 

 aggregate membership of over eight thousand;' nearly all of 

 these members are actively contributing to the advancement of 

 chemical science, publishing their results for the most ])art in 

 periodicals esi)ecially devoted to the subject. Excluding Trans- 

 actions of Societies, and Journals of Physics and Pharmacy, these 

 chemical i)eriodicals issue annually about twenty thousand pages. 

 Bearing these statistics in mind, ai'e we not justified in feeling ap- 

 palled at the idea of presenting within the compass of an even- 

 ing's address a review of Kecent Progress in Chemistry? Any 

 attempt to do more than glance at a few salient points is obvi- 

 ously out of the question. "Kecent^' time will of necessity be a 

 somewhat variable (piantity. its limits being determined by ex- 

 pediency. We shall also endeavor to bear in mind the fact that 

 we address an audience not exclusively composed of professional 

 ■chemists. 



(3.) Much interest is commonly attached to announcements 



