exjieriiiients, I'itlur not piTleotly exact, or not sullicii'iitly rin'oroiis, will serve only 

 to interrupt its protji'ess, instead of eontributing to its ailvaneemeiit." 



During tlie stormy (lays of the Revolution, as well as before, Lavoisier ren- 

 dered frequent serviees to his country. In 1787 he was eleeted to the Provincial 

 Assembly of Orleans. In 171K) he was a member of the commission which devised 

 the metric system of weights and measures. In 1791 as a member of a commis- 

 sion hi' published an essay on the National Resources of France, which entitles 

 him to high rank as a political economist. These facts show that he was a man 

 of broad interests as well as a chemist of preeminent rank. 



Some of iiis [»ublic acts, and es[)ecially those in connection with the collection 

 of taxes rendered it easy to find some trivial complaint against him. And during 

 the reign of terror, while the power of Robespierre was at its height, a trivial 

 complaint was eiiuivalent to condemnation. After sentence he asked for a fort- 

 night's delay that he might complete some scientific experiments, but with the 

 words "We have no more need of philosophers, " he was hurried to exei'ution. 

 So died, on May S, 17!»4, the greatest chemist of the eighteenth century. I had 

 almost said of any century. For we can scarcely lind in the history of thought 

 another who has so transformed the science with which he worked. He cleared 

 away the misconceptions and erroneous speculations of centuries and, building on 

 a solid basis of experimental facts, he laid a sure foundation for rapid and per- 

 manent growth in chemical knowledge. 



PAPERS READ. 



Some Factors in the Distribution of Gleditsciiia Triacanthos, and Other 

 Trees. By Ernest Walker. 



The importance of winds as factors in the distribution of plants has always 

 been recognized by all who have written on subjects connected with plant-geogra- 

 phy. It seems, however, that their effectiveness has been appreciated only in the 

 case of extremely tine and light seed, or those provided with aj)pendages for sus- 

 pension in air, while in the case of heavier seeds, unprovided with such append- 

 ages, they are held even by many of our most authoritative writers to be of little or 

 no (•onse(iuence. .Such seeds are thought to be too heavy to be affected in the least 

 bv anv wind short of a "violent storm" or leal "hurricane." As these are only 



