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BULLETIN OF THE NATURAL HISTORY SOCIETY. 
76. — On New Aneroid Measurements in New Brunswick 
IN 1903. 
Read December i, 1903 
During July, August and September, 1903, I made a number 
of aneroid measurements of the heights of places in the Province, 
mostly hitherto unmeasured, with the results below. The instru- 
ments and methods were identical with those earlier employed, 
as recorded in Notes Nos. 53 and 62. I may repeat the opinion 
earlier expressed, that the results thus obtained are as accurate 
as can possibly be secured with aneroid barometers under New 
Brunswick conditions. A few measurements made on the 
Oromocto are recorded in my note on that river (No. 73) ; I shall 
here consider only those made in the Tobique-Nepisiguit region. 
In Note No, 62, I called attention to the fact that all heights 
cliecked from the Chatham base averaged lower than when check- 
ed from the Fredericton base, and that the figures show an aver- 
age difference between the two stations of about thirty-two feet, 
which ought not to exist. As I had found reason to consider the 
Fredericton station as without sensible error, I attributed the 
discrepancy to some peculiarity in the methods or instruments of 
the Chatham station. I find the same difference this year, though 
larger in amount, reaching thirty-eight feet, but I have also dis- 
covered the explanation in part. comparison of certain figures 
shown me by Mr. D. L. Hutchinson with the daily weather maps, 
suggested that there was a real difference in the average prevail- 
ing barometric pressure, independent of elevation, of the two 
stations, and this is confirmed by the pressure maps published in 
the latest Report of the Chief of the United States Weather 
Bureau, which show that the average barometric sea-level pressure 
through the year is less at Chatham than at Fredericton. The 
average difference, however, in August, according to the latter 
map, is not over .0125 of an inch, which answers to about ten 
feet, leaving a discrepancy of about twenty-five feet to be account- 
ed for in some other way, a subject which deserves investigation. 
The practical question now arises as to the value to be given the 
readings of the two stations respectively, in determining the alti- 
tudes. Since all of the more important measurements were made 
