123 APPENDIX A.—PROGRESS OF THE SURVEY. 
I considered it necessary to demonstrate practically the character of the route, by taking a 
wagon train for the supplies. The main part was sent, under charge of Lieutenant Beckwith, 
on the Arkansas road, and, with one team, I proceeded by the Kansas to the Smoky Hill valley, 
and nearly direct in a westerly course to Walnut creek, on new ground much of the way, where 
l found a very eligible site for any description of road. Thence my route was along and in the 
vicinity of the Arkansas to the Apishpa creek, where I crossed the river, and explored the 
Huerfano country up to the pass of El Sangre de Cristo. The train passed over the usual mountain 
track, but, after a careful reconnoissance, I found a very low depression in the mountain ridge, 
by way of a small creek of the Huerfano valley, which makes the crossing very easy into the 
valley of San Luis, provided a little labor is bestowed to cut the small bushes and level the 
banks on the creek. It requires much labor on the higher pass, and also to cut the road out on 
the Sangre de Cristo creek. And on the unbroken track generally, the work has been severe in 
the mountain region, particularly for sixty miles along Grand river, where we were forced over 
a connecting mountain between the EIk and San Juan mountains. 
The Musca (Robideau) and Williams' passes were reconnoitred, and found very inadmissible 
for roads. 
I heard of and explored one, however, at the head of San Luis valley of the Del Norte, which 
led down the Puncha creek to the Arkansas plains, above its first cañon, or defile. The approach 
to it would be either by way of the Wet Mountain valley and Hardscrabble creek, or, if found 
practicable, through the defile along the Arkansas. It is far superior to either the Musca or 
Williams' passes for crossing the dividing ridge. 
The Coochetopa Pass was not very difficult for our teams, and thence to Grand river the 
descent was easy. "Thatriver runs in deep gorges, with only now and then a small valley, which 
forced us upon the rocky hills, cut through transversely by creeks, whose gullies were difficult to 
cross without much labor. This delayed us considerably on sixty miles to the Uncompahgra, 
since arriving at which our route has been easier, but we have lost the fine grass that kept our 
animals in good condition up to that point. The Grand and Nah-un-karea rivers are large, rapid 
streams, and only at low stages can they be easily forded. 
A summary result may be thus stated of the operations: One thousand and fifty (1,050) miles 
en route travelled with 18 wagons; 520 miles of new road made on unbroken ground; 4 rivers 
(besides smaller streams as difficult) ferried or forded ; 79 new or rare varieties in the botanical 
department in the plains, and 48 in the mountains; 27 varieties of mammals and birds; 26 of 
reptiles and fishes; 50 or 60 of insects; 213 observations for astronomical stations. 
The topography of the line, and all the prominent hills in sight, are taken and daily plotted 
with approximate accuracy. 
The geology of the route has also been carefully noted, and specimens collected. 
The Utah Indians have appeared friendly, and the health of the party has been pretty good. 
I secured the services of A. Leroux and Michael, two of the most competent men in the 
mountains, who are to take us to the Spanish trail; from thence I shall be without a guide. 
They are to return in a few days to Taos, and by then I expect to forward my dispatches. 
Most respectfully submitted : 
J. W. GUNNISON, 
Captain Top. Engineers, in charge of. C. P. R. R. Survey. 
Colonel J. J. AnEnT, gad 5 
Chief Topographical Engineers. 
