470 Letter from B. A. Gould. 
Thus if we denote by 7 the relative number corresponding to 
the mean s inpeniarcs as observed, to have been 16°°47 in 1870, 
and 17°°51 in 1875, while those which result from the formula are 
16° shee sae 17°49 memset. The difference 0°°16 for the first 
and the excessive deflection of the mean direction of the wind in 
1870 afford what seems to me a sufficient explanation of the rela- 
tive largeness of the residual. 
It is manifest that if the variations of the terrestrial tempera- 
d 
ndence observed bet 
variations of the magnetic declination, all necessity for assuming 
any direct and transcendental o-eimeti wid gti this latter and 
It is a source of regret that 1 have oot at disposal here any 
i nn me t 
which the investigation may be made, viz: Bahia Blanca, just to 
the north of the Patagonian coast, and this I intend to investigate 
as soon as time and gc ascercvee 
rai 
or in other in that component of the mean annual direction 
belonine is spepeodionias to the meridian. Se ag conan without — 
fon. 
periods are respectively a quart er saa the third part rt of pee 
elr existence 
2 es Wg and yet more “marked cycle shows itself in ate 
frequency of the storms, which are so well known and charac 
teristic of the La Plata. Whether we consider the annual num- 
ber of winds of force five, or six, or seven and ut wards, or the 
mean supnal. force, the same result manifests itself, viz: a periodic 
