The San Francisco call., 1909-10-03
Answers to Queries

THE TRADE wINDs-E. H., Halfmoon Bay,
Cal Tell about the trade winds and why they
are so called.
Constant winds are usually called
trade winds. When the surface heated
is, roughly speaking, a whole zone, as
in the case of the tropics, a surface
wind will set in toward the heated
tropical zone from both sides, and, unit
ing, will ascend. and then separating
will flow as upper currents in opposite
directions Hence surface current
viii flow from the higher latitude to-
ward the equator. and an upper current
toward the poles. If. then, the earth
were at rest, a north wind would pre-
vail in the northern half of the globe.
and a south wind in the southern half.
But these directions are modified by the
rotation of the earth on its axis from
west to east. In virtue of~this rotation
OBJECTS on the earth's surface at the
equator are carried round from the east
at the rate of II miles a minute. But
as we recede from the equator, this We
locity is continually diminished; at
latitude so degrees it is only eight and
half miles per minute or half of the
velocity at the equator, and at the poles
IT is nothing. A wind, therefore blow
ing along the earth's surface to the
equator is continually arriving at
places which have a greater velocity
than itself Hence the wind will lag
behind, that is will come IN against
places toward which it blows. e. will
become an east wind. Since, then, the
wind north of the equator is under the
influence of two forces-one drawing
IL south, the other drawing it west-it
VIII, By the law of composition of
forces. flow in an intermediate direc-
tlon, that is, from northeast to north
west. All observations confirm this rea-
~
tnese winds render to navigation they
nave been called the trade winds IT
is only in the Pacific and Atlantic
oceans that the trade winds have their
full scope.
BRITISH MAYA. b., Port Costa.
Cai. A correspondent in letter to
lhls department gives the following
method adopted in England in the mat
ter or furnishing men for the navy
~ ~Wheh the men are not picked up off
me street: Excepting for stoker class,
al other classes are entered as boys
are educated and trained and after
three years on a training ship are
passed for duty. Excepting those
whose ability is marked These are
allowed to spend an additional year in
lhe Sunnery and torpedo departments
IN passing these are allowed additional
l.
enter the navy of Great Britain for 2
years, three of which are spent in the
training ship and nine in the service.
At the expiration of II years they may
fe-enllst and serve on for pension
Boys who can qualify and are able to
present recommendations enter into
training at from. 13 to 16 years and are
passed into the navy from 6 to 10. The
navy is thus filled with young mon
from 16 to 2S years. About 5000 are
entered yearly for the navy.
ToUCHsToNE-F. 7. D.. City. How is gold
tested by means Of what is known as the touch,
stone? ~ Si
When it is impossible to test gold bv
the assay method in order to ascertain
its fineness it is determined by touch
stones This method is known as the
assay of the touch" In the first place
touch needles are made in sets of
gold of different degrees of fineness
and differently alloyed with silver and
copper. The touchstones are of black
basalt, marked with the piece of gold
to be tested, and when it compares with
the mark of particular needle it is
of that degree of fineness. Al further
test can be made by heating the touch |
stone TO redness and moistening the
marks with aqua fortis, their appear
anee resulting from oxidization show
ing the nature of the alloy in the sub !
stance tested. The wholly relia- !
BILE test of the fneness of gold is by
the assay process.
cRESTs-C. c. E., City What steps are |
necessary to discover ones family crest?
If you mean by this question
whether the family name had a crest
you may discover that by looking oyer
the books on crests in the free public I
library or else consult those who make I
it a business to look up ancestry. but |
as the latter are engaged in a private |
business this department can not ad-
vertise them.
sFLEAs--C. ]. T.. Oakland, Cal How may |
feas be exterminated?
One who has been annoyed to death {
with ffeass says: Our house was alive
with heas and / got rid of them by /
using gasoline. 1 got a large oil can. /
filed it with gasoline and sprayed the 1
floors and carpets and in fact every I
thing in sight. The gasoline did not I
injure anything. The odor soon disap- I
peared and so did the fleas."
CoTTON-E. A. H.. City. Which country /
produces the most cottoni
The figures for 1907-0S show: Amer
lea, 12,117,0a0 bales: East Indies. 1885,
900 bales. and other countries, $4,000
bales.