Report of the U. &. Coast Survey for 1883. 51 
improved with experience. We may, therefore, judge the 
character of these observations when we know that not a single 
member of the party at Point Barrow had ever made the sim- 
plest determination of a magnetic element when assigned to this 
work. That the observers obeyed orders and did the best they 
could is not to be doubted for a moment. Nor is it any less 
certain that they were all inexperienced in magnetic work, and 
that therefore their observations are bad, many of them very 
. The extraordinary torsion correction, for the proper deter- 
mination of which no proper data were furnished and which 
amount to 54°! in some cases, will illustrate the difficulties con- 
fronting the author beginning his reductions and \ compu- 
tations, 
e finaily adopted values of the magnetic elements at the 
Station from all the observations available, are, 
Declination 35° 37'°2 E. (Epoch Mar. 1, 1883), 
Di 81° 23'-4 Epoen October, 1882), 
Hor, force (Br. units) 1939 (Epoch October, 1882). 
The results for absolute declination as derived from the com- 
putations by the observers themselves varied from 854° to 
414°; but for the greater part the mean declination obtained 
was abont 414° EK, he value which from a comparison of all 
the conflicting data Mr. Schott has been obliged to adopt is, as 
above given, some 54 degrees less than this. 
The report of Asst. Edwin Hergesheimer on standard topo- 
graphical drawings consists of two pages of letterpress and 16 
topographical drawings which are designed and execatedl as 
Models for the use and guidance of those engaged in t»po- 
graphy. The author himself says they are designe! as 
guides for inking the original plane table sheets of the O»ast 
and Geodetic Survey,” in other words as model sheets. As 
evidence that they satisfy this requirement it may be said that 
already two large technical schools in this country have ordered 
@ large number of copies of this report for use as a text-book 
M topography. Excellent as are these drawings, even alter 
their transfer to the stone, the impressions from the original 
‘Copper plate are yet more satisfactory, while the original draw- 
mgs of Mr. Hergesheiier represent the highest attainments 
thus far achieved in topographical representation. 
ppendices 15 and 16 contain brief reports on the Tran-it of 
Mercury in 1881 and of Venus in 1882, while appendix 17 is a. 
ref report by E. D. Preston, consisting of a statement of the 
Work done by him in connection with the observations o/ the 
Solar eclipse of May, 1883. 
Appendix 18 is a new, revised and enlarged edition of Prof. 
David on’s catalogue of time and ecircumpolar stars publixtied 
