OF THE UNITED STATES. 385 



mode of j)acking to the usual one, which requires the instru- 

 ments to be dismounted. 



On the Mechanical Organisation oja Large Survey, and the 

 Particular Application to the Surveti of the Coast. 



Though the matheinalical theory of sucii works is fully 

 treated and well known, their practical applicatiun is left com- 

 j)lete]y to the practical nian ; and the success and accuracy 

 depend in a great measure on the organisation, and tiic dif- 

 fcient details of airangemcnt, which such a work requires. 

 It may therefore be useful to give here some practical prin- 

 ciples on tliis subject, in order to guide the operator in taking 

 proper advantage of the time and circumstances, and to 

 overcome the diiricullies which arc always to be met with in 

 practical works. 



The application of tliesc to the survey of the coast may 

 serve as an example, which at tlie same time will give sucli 

 information with respect to tiiat part of the work which I 

 have executed, as may enable the operator to take advantage 

 of it. or to continue it in future. 



The leading features of the general organisation arc ex- 

 posed in the plans of operation which 1 presented to govern- 

 ment j ant! now inserted in these papers ; and of which the 

 present will show the more detailed application. 



The (hst operation is of course to tlnd a |)ropcr ])lace Ibr 

 a line of sulVicient length tofornt the base of the triangulation, 

 in such a situation as will enable the surveyor to arrive by 

 simple operations and with accuracy to the determination 

 of a distance between two elevated points, in a favf)ural)lc 

 position relative to the surrounding mountains and the coun- 

 try at large. If these points be at the same lime the liiglu'st 

 and freest in the n«'ighl)ourhood, the multiplication of the 



