BAROMETRY. 



The instrument used in the earlier period of these observations 

 was made by J. S. F. Huddleston of Boston, Mass. It was 

 twice compared with a standard instrument, and the error was 

 regarded as small enough to be negligible, but was considered 

 when making the observation. In later years the barometer 

 used was one manufactured by James Green of New York City. 

 It had an error of 0.003, and this error was always considered 

 in recording. Recent standardization shows this barometer to 

 have a negligible error. The times of observation was 7 a. m., 

 2 p. m., and 9 p. m. The altitude above sea level, as determined 

 by means of the spirit level, was 134 feet from January, 1869, 

 to June n, 1879, and 129 feet from that time to January, 1893; 

 during the remainder of the period to the present time it was 148 

 feet. The dates of the missing records were as follows: 1869, 

 June and December; 1893, two-thirds of January; 1895, Jan- 

 uary and December ; 1896, January, February, and June. From 

 October, 1899, to 1903, inclusive, observations were made at 2 

 p. m. only. The latitude of the place of observation was 44 54' 

 2" N., and the longitude 68 40' 11" W. 



The means published herewith have been reduced to the 

 standard instrumental temperature. The latitude is 44 54' 

 north and altitude small ; therefore the gravity corrections may 

 be neglected as being probably zero. The observations have 

 been reduced to sea level by the formulae and tables given in 

 the Weather Bureau Instructions- to Voluntary Observers. In 

 order to take annual and other means I have thought it best to 

 give in italics the best values I could obtain by interpolation 



