Ivi PROCEEDINGS OF THE CENTENARY MEETING. 



K. Akademie van Wetenschappen te Amsterdam. 



The members of the Koninklijke Akademie van Wetenschappen at Amster- 

 dam welcome the opportunity afforded by the celebration of the Centenary of 

 the foundation of The Academy of Natural Sciences of Philadelphia to send their 

 cordial greetings to their colleagues in America. 



During the past hundred years The Academy of Natural Sciences of Phila- 

 delphia has contributed generously to the progress of scientific thought and 

 has occupied a distinguished place among the institutions of a country which has 

 rapidly placed itself in the van of scientific research. 



The constantly increasing intercourse between the scientific world of America 

 and Europe is an earnest testimony of the growth of the spirit of good will and 

 friendly emulation which stimulates the march of progress in all departments 

 of scientific thought. 



It is in this spirit that the members of the Koninklijke Akademie of Amster- 

 dam express the confident hope that The Academy of Natural Sciences of Phila- 

 delphia will fulfil with equal distinction in the future as in the past its noble 

 mission of enlarging the domain of truth and knowledge. 



H. A. Lorentz, 



President. 



J. D. VAN DER WAALS, 



Secretary. 

 Amsterdam, March, 1912. 



Exquisitely engrossed and illuminated on folio sheet in a satin-lined cylindrical 

 case with gilt clasps. 



