1877.] 



President's Address. 



439 



has just been made of the measurement of all stars in the northern 

 hemisphere brighter than the 6th magnitude, whose positions have not 

 recently been determined with precision. 



Time-signals for the meridian of Boston are sent by telegraph every 

 two seconds from the Observatory ; they are used by the local railways, 

 are transmitted oyer a large area of New England, and they strike the 

 noon-bells in Boston and in many of the smaller towns. 



Besides the above, several thousand observations for atmospheric refrac- 

 tion were made, with the assistance of the Bumf ord Committee, during last 

 summer with a micrometer level, simple in construction and accurate 

 and rapid in action, invented by Mr. Pickering. 



United States' Scientific Surveys. — Of the many surveys of the United 

 States territories undertaken, some by the Central Government, others 

 by State governments, and still others by private enterprise, more or 

 less aided by public funds, none has effected so much for science as 

 that directed by Dr. Hayden. Its publications, distributed with great 

 liberality, are in every scientific library, and its Director is honoured no 

 less for the energy and zeal with which he has laboured as a topographer 

 and geologist, than for the enlightened spirit in which he has sought to 

 render the resources of the Survey available for the advancement of all 

 branches of natural knowledge by every means in his power, and with 

 admirable impartiality. 



Having obtained an extended leave of absence from my official duties 

 at the Boyal Gardens, I, at the close of our last session, accepted an invi- 

 tation from Dr. Hayden to join his survey, and, in company with our 

 Foreign Member, Prof. Asa Gray, to visit, under his conduct, the Bocky 

 Mountains of Colorado and Utah, with the object of contributing to the 

 records of the Survey a report on the Botany of those States. 



I have thus had some opportunity of learning for myself the extent 

 and value of the operations of the Survey, which are so interesting that 

 I venture to think a brief sketch of its rise and progress and a few of its 

 results may be acceptable to you. 



When the territory of Nebraska was admitted into the Union in 1867, 

 Congress set apart an unexpended balance of .£1000 for a Geological 

 Survey of the new State ; and Dr. Hayden, then a young man who had 

 distinguished himself as an indefatigable palgeontological observer and 

 collector (in various expeditions since 1853), was appointed to conduct 

 it. In 1868 the operations of the Survey were continued, and carried 

 westward into the Bocky Mountains of "W yoming, the rich Tertiary and 

 Cretaceous beds of which were examined and described in detail, and the 

 famous Yellowstone district, with which Dr. Hayden's name will ever 

 be associated, was reconnoitred. The value of the Survey was imme- 

 diately appreciated, and in 1869 a large appropriation was voted by 

 Congress for placing it on its present footing under the supervision 



