THE ACADEMY OF SCIENCES, PARIS 97 



facility in the use of the Latin language and his skill in reporting the 

 opinions of others. He remained in office till 1699, when he was suc- 

 ceeded by Fontenelle. It was eminently fitting that he should write a 

 history of the academy as he had known it. Couplet was the first 

 treasurer and the keeper of the instruments used in experiments, an 

 office in which he was followed by his son ; Couplet had been a me- 

 chanical engineer. Early in 1667, Perrault prepared a room in a 

 laboratory placed at his disposal for the study of physics. By careful 

 experiment he fitted himself for the study of comparative anatomy and 

 vegetable physiology. The motive to these studies was curiosity rather 

 than the thought that the knowledge obtained would be of profit to 

 any one. The problems deemed most important were those of astron- 

 omy and geometry. Hence for a long time astronomical studies re- 

 ceived the greatest honor in the academy, and outside of it. Tt is, 

 therefore, not strange that tlie men who devoted themselves to these 

 studies should consider themselves superior to their fellows. They 

 were zealous for their department and paid little attention to what was 

 done in other departments than their own. For a full generation there 

 v/as ill feeling between members of the academy caused chiefly by dif- 

 ferences of opinion in reference to scientific subjects. Yet advance was 

 made in other departments than those of astronomy and mathematics. 



Du Clos and Bourdalin analysed certain salts and observed the 

 changes constantly taking place in many bodies. Mineral bodies were 

 carefully examined. Denis Dodort sought to determine the virtue of 

 plants by chemical analysis. Vegetables he tested by fire and ob- 

 tained what he and others called caput mortuum. The worthlessness 

 of this method was pointed out by Mariotte in 1679 in his essay on 

 vegetation. Many abortive efforts were made by the academy to obtain 

 fresh water from the salt water of the ocean. Special attention was 

 given to a study of the vacuum, de la Hire studied the chemistry of 

 color, du Clos and Dodort the history of plants, the result of which, as 

 has been said, published in 1676, brought great honor upon the acad- 

 emy. Dodort showed much skill in all his observations. His errors 

 were only those of his time. 



The plans of the authors of this volume embraced a complete his- 

 tory of plants. The great lack was knowledge of the physiology and 

 chemistry of vegetables. All naturalists were what are now called 

 amateurs. They gave attention to many subjects. Thus Frenicle read 

 a paper in 1660 on insects, pointing out in particular some changes 

 observed in the caterpillar. Mariotte brought out a theory of vision 

 which was strongly opposed as unscientific by Pacquet and Perrault. 

 He wrote on hydrostatics also. Strenuous efforts were made, for a 

 number of years, to measure the height of the pole at Paris. It was 

 observed that the pendulum beat with differing degrees of rapidity at 



VOL. LXXX,— 7. 



