
ON THE REDUCTION OF METEOROLOGICAL OBSERVATIONS. 85 
viz. Quebec, Montreal, Gardiner, Burlington, William’s College, Albany, 
Boston, Providence (Rhode Island), New Haven, Middletown, Western Reserve 
College (Ohio), Flushing, New York, Baltimore, Cincinnati, Natchez, Wash- 
ington, and St. Louis (Missouri). These stations form the main body of this 
group, and the only one with which it is possible to deal connectedly. In 
addition to these, as outlying points, five terms have been observed by Cap- 
tain Owen and one by Mr. Lees at the Bahamas, and eight by Captains 
Beechey and Belcher at various stations along the west coast of Mexico and 
Guatemala down to Panama and the Gulf of Guayaquil. Had these terms 
been observed simultaneously it might have been possible to connect them 
with those of Bahama into a distinct West Indian group. But the utmost 
amount of simultaneous terms which can be mustered in such a group is in 
that of September 1836, in which a single series by Mr. Schomburgk in 
British Guiana is recorded, forming with those of Captain Owen and Captain 
Beechey a triangular group, having its angles at Guayaquil, Bahama and 
Ohreala, an area far too extensive, and in which, on comparison of the 
curves, nothing can be made out but a want of correspondence in every fea- 
ture but the diurnal oscillations, which in all three are very conspicuously 
marked. A single term at Sitka, in Norfolk Sound, on the N.W. coast of 
America, observed by Captain Belcher, is equally incapable of being brought 
into comparison with every other series. Its curve is remarkably flat and 
even, rising with some degree of agitation towards the end of the term, while 
all the observations in the United States indicate a sudden and rapid fall, ex- 
tending over the same hours. 
The greater part of the terms of the American group of the United States 
and Canada have been carefully examined and discussed by Mr. Birt, whose 
remarks (in his own words) I shall subjoin sertaéim, confining my own obser- 
vations to points which he has not touched on, and to terms which are not 
included in his notes. 
North American Group. 
December 1835.—This term affords only two series—from Albany and 
Montreal, the curves of which, with a good deal of irregularity, maintain a 
coarse parallelism and agree in a tendency to rise at the end, which is much 
more decided at the latter than at the former station. 
’ For the terms of 1836 and 1837, and March 1338, Mr. Birt has drawn out 
the following Table, which exhibits the barometric ranges during 27 and 37 
hours respectively, with a view to the elucidation of the law of oscillation as 
referred to centres of greatest and least excursion. As regards this subject 
I may remark generally, that the stations, Montreal, Quebec and New York, 
but most especially the last, appear remarkable for the smoothness of their 
barometric curves as contrasted with the rest; but this is in great measure 
owing to the observations at these stations having been made at larger inter- 
vals, 2, 3, and often 4 hours. 
I have completed the table for the remainder of 1838. 
“ Tabular View of the Ranges of the Barometer for 27 and 37 hourly obser- 
vations at the Equinoxes and Solstices in the United States, during the 
years 1836, 1837, and part of 1838. 
Storm Curves. March and December 1836. 
March 1836. ya eat e December 1836. 2 PSM 
Anterior or Eastern New York..... secee “837 1935 
portion of storm. New Haven .......- ‘966 1:007 
Montreal .......... ‘241 ‘285 | Flushing .......... 1-039 1:042 
