Miscellanies. 185 



down to other observations. It would be best, therefore, that the 

 director should be allowed to regulate his own establishment. 



Large observatories, like those of Greenwich, Konigsberg, and 

 Dorpat, require, in the present state of science, large telescopes, the 

 art of dividing having been carried so far, that small instruments will 

 not answer. The necessity for large telescopes for the meridian in- 

 struments, as well as for other uses, renders such an establishment 

 very costly, and requires that it shall be independent of others. It 

 appears not to be the intention, at present, to erect such an observa- 

 tory in the United States, and details in regard to it are therefore 

 unnecessary. 



But smaller observatories may also be useful to science, especially 

 for geographical purposes. Such a one, for example, as would be 

 furnished by a room with a solid foundation, connected with a second 

 having a free horizon. The first to have cuts north and south and 

 east and west, the second to have a turning dome. The following 

 named instruments would be suitable for such an observatory. 



1. A meridian circle with a 42 inch telescope and 



20 inch circle, - - - - 



2. A telescope of 72 inches focal length, 



3. An astronomical clock, - - - 



4. A chronometer, - - - - 



5. Small transit instrument, 



6. Small telescopes, barometers, thermometers, 



&c., a theodolite, «fec, - - - 



3,900 



or about $3,000- 



A small observatory would thus be furnished for about three thou- 

 sand dollars. 



Determinations of the places of stars and planets, and even of the 

 asteroids, may be made with the circle as far as the power of the tele- 

 scope permits. Director Hansen, at Seeberg, and Professor Schwerdt, 

 at Spire, have made excellent observations with a similar instrument. 

 Observations of moon-culminating stars for longitude may be also 

 made with it. 



Observations of more difiicult objects, except perhaps the nearest 

 double stars, of comets, for the exterior of the planets, &c., may be 

 made with the larger telescope. 



The small transit instrument, placed east and west, will give the 

 latitude within limits depending upon the accuracy to which the 

 declinations of the stars are determined, and in conjunction with the 

 chronometer, will serve to determine the geographical positions of 

 places which may be selected. For longitude, observations are made 



Vol. xxsviii, No. 1.— Oct.-Dec. 1839. 24 



