526 POPULAR SCIENCE MONTHLY. 



The academy suffered from the seven years' war (1756-1763), but 

 its regular work continued, though few new members were added during 

 this period. From 1760 to 1764 no 'Memoires' were published. 

 While Maupertuis was absent on account of the wars and in search of 

 health, Euler acted as president, and proved himself well qualified 

 for the duties of that office. But the king had no intention of filling 

 it with a German. The man he wanted was d'Alembert, of Paris, to 

 whom he offered a large salary, rooms in the palace and a seat at the 

 royal table if he would come to Berlin. But d'Alembert belonged to 

 the French Academy and did not care to leave Paris. Yet, through 

 his correspondence with the king, in which during these years the best 

 history of the academy is found, he directed the work of the German 

 academy and determined its membership. Virtually he was its presi- 

 dent, though the king as its protector may be said to have assumed that 

 office himself. In these conditions the academy became more French 

 in its spirit than ever. In spite of the fact that the forty-six years of 

 Frederick's academy were years of the first importance for the develop- 

 ment of science and literature in Germany, neither the king nor his 

 French presidents took any notice of the new spirit which had arisen 

 among the German people, and had begun to show itself in the academy. 

 Euler, disappointed at the turn matters had taken, after twenty-five 

 years of hard work in Berlin, asked leave to return to St. Petersburg. 

 For a time the king declined to grant the request, but its renewal finally 

 secured his assent, though without any recognition of the fame Euler 's 

 attainments and publications had brought the academy and Berlin. 

 Ten years later, on accepting honorary membership in the St. Peters- 

 burg Academy, at that time a rival of tic Berlin Academy, the king 

 wrote Euler a letter accepting the honor secured for him, and in it 

 made something like an atonement fcr former neglect. La Grange, 

 of Turin, second only to Euler as a mathematician, was elected to 

 the vacancy Euler 's departure had made, and about the same time J. 

 Heinrich Lambert, another mathematician of note, came into the 

 academy. Prior to d'Alembert 's connection Avith it the Eulers, father 

 and son. Pott, Marggraff, Gleditsch, Merian, Sulzer and Suessmilch 

 had given it fame. Other men of rare ability had been persuaded to 

 come to Berlin with the promise of membership in it, but Avith the 

 understanding that they were to teach in the Eitterakademie, an insti- 

 tution in which the king took much pride and which he founded. 



Not many changes in the academy took place during the last sixteen 

 years of Frederick's reign. Between 1766 and 1770 two volumes of 

 'Memoires,' which the war had prevented from appearing, were pub- 

 lished. With the next issue a new series of 'Memoires' was begun, 

 greatly improved in binding and paper. Each of these new volumes 

 contained a brief history of the work of the year. 



