AND RETURN TO SAN FRANCISCO. 49 
and long necks of land in the midst of a vast body of 
water. While we were on the crest of the high range, 
a dense fog so completely enveloped us that we could 
see nothing but the point on which we stood. We 
made our way back much more rapidly than we came, 
it being earlier in the day and much cooler; so that 
by twelve o'clock we were at MacDonald’s place, 
where we dined and allowed our animals to feed and 
rest. | 
At half-past two we bade farewell to our kind and 
hospitable hosts, Mr. and Mrs. MacDonald, and resum- 
ed our journey. Stopped for fifteen minutes at Mr. 
Knight’s, when we again pushed on, and reached Mr. 
Kilburn’s at sunset. This gentleman was now at 
home, and gave us a warm reception. We learned 
many particulars from him corroborating the statements 
we had heard of the extraordinary fertility of the soil. 
in Napa Valley, as well as the great yield of vegeta- 
bles on his own land, of which I have before spoken. 
March 25th. Took an early start, first making 
inquiries of Mr. Kilburn about the locality of some 
hills of “ black flint” which we had heard of. We had 
occasionally picked up along the road small pieces of 
obsidian, and were extremely desirous to find whence 
they came. After many inquiries we were directed 
to the farm of Mr. Kelly, who has a small mill on Napa 
Creek, a short distance from the road. We found Mr. 
Kelly at home; and on making known our wishes to 
examine the place referred to, he took a spade and 
accompanied us to the spot, about half a mile distant, 
on the eastern side of the valley. We found it to be 
a spur of the mountain ridge, about eighty feet in 
VoL. 1,—4 
MISSOURI 
BOTANICAL 
GARDEN. 
