14 CARNEGIE INSTITUTION OF WASHINGTON. 



Such an engine has been constructed at the shops of the Observatory 

 during the past year by Mr. Jacomini, mechanician of the depart- 

 mental staff, in collaboration with Dr. John A. Anderson, of Johns 

 Hopkins University, who has supplied tests of precision which have 

 led to a highly satisfactory degree of perfection in this excessively 

 difficult and delicate kind of construction. It is gratifying to report 

 also in this connection that the glass disk for the 100-inch telescope, 

 which a year ago had developed distortions indicating defective sta- 

 bility, is now meeting all essential requirements and giving promise 

 of an optical surface equal to, if not superior to, that of the 60-inch 

 mirror. Accordingly, work of construction for the foundation and 

 for the mounting of this 100-inch telescope is now proceeding as 

 rapidly as the conditions of safety and of efficiency in such a novel 

 undertaking will permit. 



OUTLINE OF RESEARCHES OF THE YEAR. 



As is abundantly indicated in previous reports, and as is evident 



to any deliberate reader of the bewildering miscellanies presented in 



the Year Books, the diversity and the complexity of 



Administrative the investigations going forward under the auspices 

 Reports. ^£ ^-^e Institution preclude anything like a clear and 

 complete summary of their scope, progress, and prospective value 

 within the hmits of an administrative report. The general reader 

 must take it for granted (provisionally at least) that these investiga- 

 tions are in the main worth undertaking and thus await the verdict 

 of time through the aid of a growing critical public opinion; for in 

 proportion as such investigations are fundamental, and hence worth 

 carrying on, they will be difficult of exposition and more difficult of 

 comprehension. Concerning this matter there appears to be prev- 

 alent a popular fallacy to the effect that writers untrammeled by 

 competent scholarship, but who possess verbal facifity, are better 

 qualified to expound a technical subject than those who have devel- 

 oped it or contributed thereto; and along with this fallacy there is 

 frequently coupled another to the effect that ours is an age of nar- 

 rowing specialization, whose evil effects may be remedied by resort 

 to Uterary views of phenomena and by restricting the range of increas- 

 ing knowledge. While patiently tolerant with these extremes of 

 opinion, it is obviously inadmissible to adopt either of them here. 

 We may neither pretend to exposition of knowledge not acquired 

 nor deprecate the excess of knowledge possessed by experts in this or 

 that field of science. It is hoped, therefore, that the brief summaries 



