268 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



all the stations, and also by time meanders of all the main 

 streams, and generally by a running sketch of the routes 

 traveled. The main stations averaged one to every seventy- 

 Jive square miles of area. 



By meandering, Mr. Chittenden surveyed the San Juan 

 River, the La Plata, the Mancos, and the Dolores, all of them 

 considerable streams, and besides these also the McElmo and 

 Montezuma Creeks, which, though well-defined stream-beds, 

 contain no running water. These last-named dry rivers are 

 each upward of seventy-five miles long, and for a consider- 

 able part of their course are in deep canons. In the mean- 

 ders he made a trigonometric location as often as once in 

 ten miles. 



The great trouble in working was lack of water. They 

 were often obliged to ride out ten, fifteen, and even twenty 

 miles from the rivers to make a station, and back again for 

 camp, because outside of the rivers themselves there was no 

 water at all. 



In regard to the systems of working generally employed 

 now in the different surveys west of the Missouri River, the 

 plane table system, which was generally used this summer, 

 is admirably adapted to a low, broken country where good 

 "points "are abundant, and works also extremely well in a 

 simple canon country, where there are surrounding promi- 

 nent points at not too great distances. But in a mountainous 

 country it could not be used to any advantage, and was event- 

 ually abandoned in all the mountain work. In low, broken, 

 and canon country it is probably the best system that can 

 be used; but in the ordinary rolling and mountainous country 

 of the Northwest it will not repay the extra weight and time 

 which its use entails. 



In any but a very mountainous country a system of mean- 

 ders seems to be almost necessary to make work on a scale 

 of four miles to an inch complete. It is the abuse and not 

 the use of the old odometer system that lias brought it into 

 so much discredit. If properly checked, the meanders give 

 the more important portions of the country, as the traveled 

 routes and principal rivers, the greater degree of accuracy 

 which is their due. The third and only remaining system 

 in use in the West is that generally employed on this survey, 

 and formerly used both in the California Survey and in that 



