158 
SCIENCE. 
MOUNT HAMILTON. CAL. 
We present our readers with a view of Mount Hamilton, 
the site selected for the Lick Observatory. Previous to any 
decision being finally arrived at, Mr. S. W. Burnham, of 
Chicago, was directed to make a report upon the fitness of 
the selection for the purpose. He states that “in accordance 
with an arrangement made with the Trustees of the James 
Lick bequest to make a series of astronomical observations 
for the purpose of determining the atmospheric condition of 
that location, with reference to its adaptation for the pro- 
posed Lick Observatory (originally suggested by Prof. Ed- 
ward S. Holden, in 1874, and subsequently approved by 
Prof. Simon Newcomb, in 1879), I left Chicago on August 
10, 1879, arrived in San Francisco on the evening of August 
15, and left for Mt. Hamilton the next morning in company 
with Capt. Richard S. Floyd, President of the Trustees. 
The summit was reached during the afternoon of the same 
day. The telescope, which was already on the ground, was' 
hurriedly unpacked, temporarily set up in the observatory, 
and used that night.” 
SITUATION OF MT. HAMILTON. 
The city of San Jose, the nearest point of railroad con- 
nection from Mt. Hamilton, is 50 miles south of San Fran- 
cisco. Mt. Hamilton, by the highway, is 26 miles from 
San Jose, nearly east, and is reached by a good road con- 
structed two or three years since by the county of Santa 
Clara. In order to keep the grade within the limit of six 
feet in one hundred, the last portion of the road is carried 
up the ridges of the mountain by a circuitous route. The 
distance between the Observatory and San Jose, in an air- 
line, is only 13 miles. 
The approximate geographical of the Observatory Peak 
is: 
Longitude 121° 36' 40" W. 
Latitude 37 0 21' 3" N. 
The elevation of this point is 4,250 feet above the level of 
the sea. The north peak, which is about three-fourths of a 
mile distant, is 140 feet higher. The ridge between is 
a good trail connecting the two peaks. The sides of the 
mountain, in most directions, are very steep, and form an 
acute angle at the summit. The view from the peaks is 
unobstructed in every direction, there being no higher 
ground within a radius of 100 miles. In this connection the 
e report of Messrs. Herrmann Bros., the engineers who 
surveyed the road, will be of interest: 
“The scope of the horizon from Mt. Hamilton takes in 
more ground, according to Prof. Whitney’s judgment, than 
almost any similar peak in the United States, therebeingno 
obstruction to the view from any quarter. It is remarkably 
free from fogs and clouds, as we had ample occasion to ob- 
serve during our last winter’s stay on the mountain when 
locating the road. The bearings of the most notable objects 
are as follows, the distances being taken, when out of our 
county, from our most reliable maps: 
Mt. I.oma Prieta S. 35 0 5' W., 19^ miles. 
Mt. Thayer S. 51° 18' W., 19& “ 
Mt. Poucher S. 38° 35' W., 6 
Block Mountain S. 87° W., 27^ “ 
Mt. Tamalpais N. 51 0 20' W., 66 u 
Mission Peak N. 47 0 55' W., 16 “ 
Mt. Story N.25 0 45' W., ioj^ “ 
Mt. Diablo N. 21 0 45' W., 39^ “ 
Mt. Sautana S. 37 0 E., 35 “ 
Murphy’s Peak S. 6 ° 5' W., 15 “ , 
None of these points reach the altitude of Mt. Hamilton. 
Of those within a radius of 20 miles the Loma Prieta reaches 
3,800 feet, Thayer 3,550, and Block Mt. 2,800. All the rest 
are between 1,500 and 2,500 feet. Of the further peaks Mt. 
Diablo is 3,856. 
The formation of Mt. Hamilton, as of all the near sur- 
rounding ridges, is of trap rock. The high points, not 
worn down by the atmosphere and the action of the rain, 
are, therefore, very hard as soon as the upper crust is re- 
moved. In building the road we struck this hard rock at 
six or seven points on and near the cone, with a good pros- 
pect of finding it continuous and getting harder in the same 
proportion in going deeper. It has broken through the 
older formations at several points, near the base of the 
mountain, where it shows the same character, only inten- 
sified. At the top it appears as a greenstone porphyr, with 
small larkspur veins, exceedingly hard, without any defined 
strata, but in large boulders worn smooth, and generally 
flat on one side, and cemented together by other material 
less hard and easier to work. At a great many places the 
metamorphic slate, uplifted by the later upheavals, shows 
in considerable bodies, one of them being on the south side 
of the Observatory Peak, and nearly opposite one of the 
hardest points of porphyr.” 
At sunset the Pacific Ocean is seen over the summit of 
the Coast Range at various points, and occasionally a snow- 
covered mqpntain was seen in a northerly direction, sup- 
posed to be Lasson Butte, the distance of which is about 
175 miles. The great range of the Sierra Nevada, about 
130 miles distant, came out sharp and distinct at sunrise. 
There were many very distant peaks in the east and south- 
east which could not conveniently be identified. As an 
illustration of the transparency of the atmosphere, I may 
mention a fact communicated to me by Prof. Davidson, of 
the U. S. Coast Survey. He was at work in the Sierra Ne- 
vada, at an altitude of over 10,000 feet, and was able to see 
with the naked eye the five-inch mirror of a heliotrope 175 
miles distant. 
For a critical resume of the work done by Mr. W. S. 
Burnham upon Mount Hamilton, and the results he arrived 
at, we refer our readers to the article on “ Mountain Sites 
for Astronomical Observatories,” in our last week’s issue. 
The opinion of Mr. Burnham is summed up in the 
last words of his report when he observes that “Mount 
Hamilton would be much more desirable, and more 
could be accomplished there with a large telescope than 
at any other place where an observatory has yet been 
established. So far as there have been opportunities 
for judging, it is obviously an appropriate place for 
erecting and maintaining the telescope to be constructed 
under the Lick deed of trust, and required to be “ superior 
to, and more powerful than, any telescope ever yet made.” 
With such an instrument in such a field wonderful discov- 
eries may be made. The only limit to the size of the object 
glass would be found in the mechanical difficulties attend- 
ing its construction. No refractor that can be made in the 
present state of the art would be unsuitable, so far as the 
observed conditions would enable one to judge. It is im- 
possible to overestimate the great discoveries which might 
be made and the important work done with a first-class ob- 
ject glass of thirty inches or more aperture, as perfect in all 
respects as the instrument at the Naval Observatory at 
Washington.” 
