342 W. Ferrel—Meteorological effects upon the Tides. 
other. 
Art. XXXVIL. — Meteorological effects upon the heights of the 
Tides; by Wu. Ferret. Letter to Professor BENJAMIN 
Perrce, Superintendent U. S. Coast Survey. (Communicated 
by the author with the authority of the Superintendent of the 
Coast Survey.) 
Camprince, Mass., Jan. 2, 1873. 
meteorological records of Cambridge Observatory for the same 
years, the corresponding barometric pressures and the directions 
and forces of the winds were obtained, and collated with the 
residuals. The range of the barometer was then divided into 
seven parts, and all the barometric pressures belonging to eac 
one of these divisions were grouped together, and likewise the 
corresponding tidal residuals, and the averages taken and com- 
pared. High and low waters were at first kept separate, but the 
results subsequently combined. The observations also when 
the pressure was increasing, and those when it was decreasing, 
were kept separate in order to determine whether there 1s any 
perceptible difference on account of the inertia and the friction 
of the water in it from assuming at once the condition 
of static equilibrium. The following table of combined resu 
of high and low waters were thus obtained. 
Ristne BAROMETER. ! FALLING BAROMETER. | AVERAGES. 
No. | Baromet- Tidal No. | Baromet- Tidal Baromet- |__ Tidal 
Residuals 
tol wee Cee et ee ee ee tae 
Brckacune 
158| 297500) +0-307|| 279| 29-480; +0-320} 29°487) +0°315 
363) 29-7 0°152|| 569} 29-717; 0-212) 29°713) 0.192 
449, 29842) 40-0501 519| 29-843! 0-082 0-067 
662) 29°943) —0-030'| 695) 29-940! +0-025 29°942| +0°00 
887} 30°053;  0°062|| 820! 30-050) —0-035| 30°052) —0°04' 
962; 30°197/ 0°115'| 845' 30-190'  0°125'| 30°195| 07120 
| 628) _ 30-420) —0-260)| 472] 30-415 —o-240/| 30-418] __ 0-251 
