28 CARNEGIE INSTITUTION OF WASHINGTON. 



Rhode Island, and New York have been printed during the past year; an 

 index for the State of CaHfornia is now in press ; and other vohimes of this 

 series are in preparation. 



During the past year the equipment of this novel establishment has fol- 

 lowed close after the completion of its construction, announced in my pre- 

 ceding report ; and it may now be said that the plant and 

 ^^Laborrttr'^^^ ^^^^ ^^^^ ^^ *^ Laboratory have attained substantially the 

 standard of opportunity and efficiency desired. Hence- 

 forth, therefore, the staff may devote its energies to a systematic study of the 

 origin and transformation of the rocks of the earth's crust by the aid of 

 appliances adequate to cope with the actual conditions of the difficult prob- 

 lems to be solved. The two principal features of these appliances are those 

 which render available as adjuncts in research high pressures and high tem- 

 peratures, separately or in combination, as may be desired. Hence we may 

 confidently expect from this organization results of great importance with 

 reference to well-known materials, and results of equal importance with refer- 

 ence to the more theoretical questions of the general properties of materials 

 in the earth's mass. 



In the preparation of high-pressure apparatus the Laboratory has had 

 the good fortune to secure the services, as Research Associate, of Dr. A. 

 Ludwig, of Dusemond, Germany, who has had exceptional experience in 

 this line of work. By his aid a compressor has been installed which is 

 expected to develop pressures up to 5,000 atmospheres or more. 



Simultaneously with the installation of equipment, investigations have been 

 in progress and several technical papers have been published by members 

 of the staff during the year. An outline of these papers is furnished by the 

 Director in his report in this volume, pages 97-106. 



The work of the Department of Historical Research during the past year 



has proceeded essentially along the lines laid down by the present Director 



in his first annual report, published in the Year Book for 



Department of 1006. His department has been occupied, therefore, 



Historical Research. ^ . , . , f. , .- . , , . . 



mamly ni the discovery, classification, and cataloging of 



original documents relating to American history. The field for this work 



is necessarily a wide one, requiring explorations in many foreign archives 



as well as in those of the United States. Thus, during the past year, while 



the government archives in Washington have been one of the main objects 



of research, investigations have been carried on also in the archives of 



Mexico, Great Britain, France, and Rome. 



Two specially important publications of the Department have been in 



l^ress during the year, namely : a new and greatly enlarged edition of Van 



Tyne and Leland's "Guide to the Archives of the Government in Washing- 



