12 REPORT OF THE SECRETARY. 



at the expense of the Institution, under the direction of Mr. C. A. Scbott. 

 Of this, 100 pages have be'en stereotyped. 



Of the octavo publications there are in press : 



1. The monograph on the American Vespidce or wasps, by Professor 

 de Saussure, of Geneva. Of this a full account was given in the last 

 report. The rapidity of printing in this case is diminished by the neces- 

 sity of sending the proof-sheets to Switzerland. The work has been 

 stereotyped as far as the 236th page, and we trust will be completed in 

 the course of a few months. 



The Botanical Index, of which a notice was given in the Eeport for 

 1S70, has been commenced, and 72 pages printed. This work is a com- 

 plete index to all the species of plants of North America, with their 

 synonyms, and all descriptions and important references to them. It is 

 intended to facilitate the labors of working botanists, especially in the 

 study of our western plants, the search for what has been written in 

 regard to them requiring in many cases nearly as much time and labor 

 as all the rest of their work. 



As a further contribution to the " Constants of Nature" mentioned iu 

 the last report, Prof. F. W. Clarke has furnished an additional series of 

 tables of specific heat and of expansion by heat for solids and liquids. 

 We have also received from our collaborator, Prof. John L. LeCoute, of 

 the University of California, a series of constants relative to the weight 

 of air, pressure of the atmosphere, length of seconds, pendulum-velocity 

 generated by gravity iu a mean solar second of time at various places, 

 velocity of sound, &c. It is the intention of the Institution to continue 

 this work, and to endeavor to en-list other co-laborers in its prosecution. 



RESEARCHES. 



Meteorology. — It was stated in the last report that the meteorological 

 system of records by voluntary observers, which had been in operation 

 under the direction of the Institution for about tweuty-five years, had 

 been transferred to the signal-office of the War Department, under Gen- 

 eral A. J. Myer. This transfer was made in accordance with the general 

 policy of the Institution, namely, that of abandoning any field of enter- 

 prise as soon as the work could be done as well through other agencies, 

 thus reserving the energy of the establishment for labors which required 

 more aid in their accomplishment. We think this transfer has received 

 the approbation of observers generally ; who also, while they are now 

 co-operating with the Signal- Service, still keep up their correspondence 

 witli the Institution on subjects of general scientific interest. The 

 labors of the Institution iu the line of meteorology are now confined 

 to working up the material which it has collected during the last 

 quarter of a century. The materials, however, are not limited to that 

 period, but embrace everything that could be obtained on the subject 

 from the records of previous observers. 



