224 General Notes. [ March, 
appeared a series of maps, comprising most of the topographical 
work of the last two years, 1877 and 1878. This series comprises 
a sketch of the primary triangulation, and a drainage map, each 
covering the whole area surveyed, on a scale of eight miles to an 
inch, a detailed map of the Yellowstone National Park, on a scale 
of two miles to an inch, and three detailed atlas sheets, on a scale 
of four miles to an inch, The last three sheets were noticed in 
the number of the NATURALIST for January. 
The triangulation sheet shows the scheme of the primary trian- 
gulation, the stations, the sight lines, the closed and open tri- 
angles, the details of the expansions from the bases, and the astro- 
nomical connections. 
e base lines were two in number, one near Fort Steele, on 
the Union Pacific railroad, Wyoming, the other in the valley of 
Bear River, near the village of Georgetown, Idaho. Each was be- 
tween five and six miles in length, about two miles of which appear 
to have been measured directly, while the balance was ranged out 
by small, well proportioned triangles. The expansions were by 
means of closed triangles, and, apparently were well executed. 
The astronomical connections were ample, consisting of stations at 
Sherman and Fort Steele in Wyoming, Salt Lake City and Ogden 
in Utah. These points were located by the Coast Survey and by 
Lieut. Wheeler of the Engineer Corps. The scheme is well 
planned, most of the triangles being well proportioned and the 
only failures are unquestionably due to the incompleteness of the 
work, owing to the abrupt discontinuance of the survey. 
Since the discovery of the wonders of the Yellowstone coun- 
try, in 1870, this region has been a favorite field of exploration. 
Expedition after expedition has traversed it, each following much 
the same routes as its predecessors, and, after the first, adding but 
little to the sum of human knowledge regarding this strange fire- 
ridden region. ; 
The explorations in this region, of the survey under Dr. F. V. 
Hayden, in 1871 and 1872, were singularly prolific of facts, geo- 
logical, physical and geographical, and little that was new was 
evolved from numerous expeditions that followed. The bi 
nuggets had been taken, and nothing but a careful, scientific, 
eworking of the tailings would extract from them the wealth of 
fine gold which they still held. popa 
In 1878, Dr. Hayden’s survey reached this region in the prose- 
cution of its system of surveys. Its work had, years previously, 
passed from the reconnoissance stage to that of systematic surveys 
on a scale and of a degree of accuracy commensurate with the 
needs of the country. : 
In that year, a party was directed to make a detailed survey of 
the Yellowstone Park, its geography, geology and volcanic 
phenomena. a 
A part of the results of this season’s work is now before the _ 
