252 PROCEEDINGS OF THE CALIFORNIA 



aids, but to the employee with the party. Upon some nights it was found as 

 soon after sunset as Polaris could be seen, the twilight being quite bright. 



Saturn. — The rings of Saturn were well divided, and the form of the shadow 

 of the planet on the rings plainly defined, whilst the brighter appearance of the 

 inner ring was plainly apparent. The markings across the body of the planet 

 were visible, but not well defined. With the planet just out of the field of 

 view, one of the satellites was visible. The body of the planet and the outline 

 of the rings were sharply defined and very steady ; no jumping, or irregular 

 motion, or blurring. These were seen by the members of the party, and eveu 

 by strangers unaccustomed to the use of a telescope. 



The Moon. — These observations revealed a distinctness, sharpness and steadi- 

 ness, for which he was wholly unprepared. When there was the slightest un- 

 steadiness in the early evening, the impression was made upon the observer that 

 a very thin, tremulous medium was between the moon and the observer, and not 

 as if a dense medium was immediately enveloping the moon, which is the im- 

 pression conveyed at moderate elevations. The cusps of the young moon were 

 traced to extreme fine lines of light, with wonderful distinctness ; these extrem- 

 ities of the cusps being apparently much finer than the finest spider thread in 

 the instruments. They were traced from three to five degrees further than is 

 ordinarily visible. There was not the least haziness, or unsteadiness, or blurring 

 about them, "i'he mountains were very sharply defined. The outline of the 

 bright limb was so steady, sharp and clear, that the irregularities throughout its 

 border could have been drawn and measured. One large elevation projected so 

 far beyond the general curve of the bright limb, that it would have occasioned 

 an error of one, or one and a half seconds, in the time of immersion of a star at 

 that place ; and all around were irregularities that would very seriously affect 

 the time of occultation of a star. When the moon was more than half full, he 

 observed the occultation of a star of the eight and a half or ninth magnitude. 

 He concluded that measures of precision upon the moon, for diameter, etc., 

 made under similar circumstances, would in one or two nights be of greater 

 value than the results of six months' observations made at low altitudes. The 

 orographical character of the border of the moon could be observed and meas- 

 ured, lie thought the transit of the ash-gray limb might be observed with fair 

 precision. The phenomenon of a star entering upon the body of the bright limb 

 before disappearing, could be well studied. Photographic pictures of the moon 

 could be made with remarkable effects. 



The Sun. — Results of equal value were observed upon the sun. The outline 

 was rcmarknbly sharp, clearly defined, steady, and free from blurring. The 

 spots and facute were studied, and the inflowing of a white stream across one 

 of the large spots. The facute were traced over the greater part of the sun, 

 and the changes in some of them noted. Around the penumbra of the largest 

 spot there was a mottled appearance, as if an intermediate penumbra existed 

 between the penumbra proper and the brighter body of the sun. The spots, 

 penumbrse, striations in the penumbra, and the facula;, might all possibly be 

 exhibited in a photograph. He made the same remarks of the relative value 

 of observations of precision under such circumstances, as he had of the moon. 



