32 CARNEGIE INSTITUTION OF WASHINGTON. 



recommendations with respect to a project for the publication at some future 

 time of an atlas of historical geography of America, for the preliminary con- 

 sideration of which a small appropriation is approvd for the budget of 

 1910. 



The work of this laboratory proceeds by means of some of the most re- 

 cent methods and appliances of research, and hence its aims and lines of 

 investigation, like those of all new sciences, present to the 



The Geophysical public more or less of obscurities of interpretation and 

 Laboratory. ^ . ^ 



obstacles to ready appreciation. The Director has there- 

 fore properly taken occasion in his report for the year to furnish additional 

 explanations of the nature and the scope of his enterprise. Referring to his 

 report for instructiv details, it may suffice here to state that the researches 

 of the laboratory afford another instance of the normal evolution of a science 

 from the observational and descriptiv stage to the higher level of measure- 

 ment and calculation. That geology and mineralogy will be much advanced 

 by such researches is now recognized and attested by eminent specialists. 

 Indeed, the definitiv results already attaind by members of the laboratory 

 staff are now finding their way into the elementary as well as into the more 

 technical literature of those sciences. 



Many publications have been issued during the year by members of the 

 laboratory staff, chiefly thru current journals, which provide easier access 

 for contributions to mineralogy and geology than to most other sciences. 



The equipment of the laboratory has receivd an important addition during 

 the year in apparatus for subjecting materials under observation to high 

 pressures and high temperatures, either simultaneously or separately. This 

 apparatus, developt by Dr. A. Ludwig, Research Associate of the depart- 

 ment for the year, will give pressures up to 17,000 atmospheres, or 250,000 

 pounds per square inch. 



The Tortugas laboratory of this department is proving highly effectiv as 

 a center for research by a wide range of specialists. Eight associate investi- 

 gators have availd themselves of the opportunities afforded 



Department of ^y ^.j^g department during the past season ; and the results 



of their studies are now in preparation for publication as 



contributions to science from the laboratory. Two important volumes of 



such contributions have been issued as Nos. 102 and 103 of the publications 



of the Institution during the year. 



A comprehensiv resume of the work of the department up to date is given 

 by the Director in his current report, and attention is specially invited to the 

 succinct and clear exposition he gives of the results attaind at the laboratory 

 by himself and by his associates. It is of interest to note the advent of quan- 



