APPENDIX. 
A. 
Gamp near Mission San Diego, 
December 20, 1853. 
Sir: I have the honor to acknowledge the receipt of instructions from the War Department, 
November 18, 1853, detailing me for the prosecution of a survey u in connection with examina¬ 
tion of railroad routes to the Pacific,” through Northern Mexico and Texas, together with the 
passport, and a copy of the instructions relative to the organization of an escort. They arrived 
at a most opportune moment; Lieut. Williamson about completing his field-work, and Lieut. 
Stoneman encamped at this place with his escort. Of Lieut. Whipple’s movements or wherea¬ 
bouts we have heard nothing definite; and I will, therefore, proceed to organize and equip my 
party, without counting upon any assistance from the latter officer, receipting to Lieut. Wil¬ 
liamson for such instruments and property as I shall need, and at the same time can be spared 
by him. 
But, to complete my outfit, it is absolutely necessary that I should go to San Francisco, 
mainly to procure barometers. This trip I shall make with all possible despatch. 
In my instructions no mention is made of either an assistant or a physician. 
Deeming both of these essential to the rapid prosecution of the work and well-being of the 
expedition, I will secure their services, in case they can be obtained at such salaries as will not 
cause my expenditures to exceed the amount of appropriation allowed me. 
Very respectfully, your obedient servant, 
JNO. G. PARKE, 
Bvt. 2d Lieut., Corps Top. Engineers. 
Hon. Jefferson Davis, 
Secretary of War. 
B. 
War Department, 
Washington , December 9, 1853. 
Sir: On the eighteenth ultimo, instructions were addressed to you at San Diego, from this 
department, to make preparations for, and take charge of a survey for a railroad route from a 
point on the Gila, near the Pimas villages, to the Rio Grande, partly passing through Mexican 
territory, for which authority had been obtained from the Mexican government. Since those 
instructions were despatched, intelligence has been received here of a hostile expedition against 
the Mexican province of Sonora having sailed from California; and it is apprehended that this 
lawless conduct on the part of our misguided citizens may excite a feeling among the Mexican 
people which would render it unsafe for your party, with its military escort, to make its appear¬ 
ance among them, especially as it is not known whether the Mexican government has advised 
its officers or people along the line of your route that the survey is made by permission. 
