AND RETURN TO SAN ‘FRANCISCO. 51 
as well as those of the Gila and Salinas Rivers. The 
Apaches had arrows pointed with the same material. 
Yet I know of no other locality where obsidian is 
found in place in any of the regions visited by the 
Boundary Commission except this. All the specimens 
we saw were black, occasionally with a smoky or 
brownish tint.* 
We now continued our journey, and reached Mr. 
Osborne’s at two o’clock. After dinner we rambled 
over the adjacent hills to obtain a better view of this 
delightful valley, which+lost none of its beauties from 
whatever point it was observed. 
On the opposite side of the mountains which 
bound Napa Valley on the west, is Sonoma Valley. © 
This is similarly situated, running north and south 
between ranges of low mountains. It likewise pos- 
sesses great, Sotidity, but has not the picturesque 
beauty of Napa. The same may be said of the valleys 
of Petaluma, Novato, and San Rafael. 
March 26th. Took an early breakfast and bade 
adieu to our kind and gentlemanly host, who intended 
to follow us in a few hours. We did not wait for him, 
as he wished to stop on the way, and I was desirous to 
pay my respects to General Hitchcock and the other — 
officers at Benicia before returning to San bigs 
* Obsidian is said by Pliny (Nat. Hist. xxxvi. 26) to have 
first found in Ethiopia by a person named Obsidius, from — 
rives its name. It occurs also in various parts 0 Pes - ue 
America, and in the vicinity of most voleanoes. Pliny : says that gems, 
and sometimes whole statues, were made of it. He also speaks of four 
_ of obsidian, ween were dedicated by — in the temple 
oO ord, 
