260 NATIONAL ACADEMY OF SCIENCES 
cessful execution the various operations necessary for photographing the transit 
of Venus by the methods decided upon by the commission, and of instructing the 
parties in those operations. Dr. Draper accepted this arduous duty, and per- 
formed it in a manner which commands the gratitude and respect of the com- 
mission. Dr. Draper declined to receive any compensation or reimbursement for 
his invaluable services and for his unavoidable personal expenses while traveling 
and residing in Washington, on the service of the commission. 
“The system of practice was fully carried out, and the several parties destined 
for the observation of the transit of Venus in both hemispheres, left the United 
States fully qualified in all respects to perform their duties. 
“Instructions for conducting the scientific operations of the parties were pre- 
pared by Professor Newcomb, printed, and freely distributed.” §* 
The Transit of Venus Commission of 1874, which was con- 
sidered as having continued in existence, took charge of the 
arrangements for the observations of the transit of 1882 and 
prepared instructions to the observers that were printed by 
authority of the Secretary of the Navy.” The Secretary remarks 
as follows in his report for the fiscal year ending June 30, 1882: 
“TRANSIT OF VENUS 
“Professor Harkness has been principally occupied in fitting out the parties for 
observing the approaching Transit of Venus, and in reducing the zone observations 
made in Chili during the years 1850, 1851, and 1852, by the astronomical expe- 
dition to the southern hemisphere, under the late Capt. James M. Gilliss. . . . . 
“ Everything relating to the organization of the Transit of Venus parties is 
confided by law to the Transit of Venus Commission; but as most of the executive 
work has been done at the Observatory, it may be proper to refer to it here. 
“The instruments used for the last Transit have been examined and repaired ; 
all necessary changes have been made in them, and some new instruments have 
been purchased. 
“At a very early stage of its deliberations the Commission decided to rely 
mainly upon the photographic method of observing, and, to ascertain the most 
suitable kind of emulsion, an extensive series of experiments was made by Mr. 
Joseph A. Rogers, who has also prepared all the emulsion needed for the various 
parties. 
Rep. Secr. Navy for 1874, pp. 68-69. 
“Instructions for observing the Transit of Venus, December 6, 1882, prepared by the 
Commission authorized by Congress, and printed for the use of the observing parties by 
° 
authority of the Hon. Secretary of the Navy. Washington, 1882. 4°. Pp. 1-50, with 
4 charts. 
