The sun. [volume] (New York [N.Y.]) 1833-1916, 1900-11-11

remembered thai The meteOre may porSipAy
fall at the rate Of more than hfty Q minute.
The record viii serve TO Identity all or at least
a great many. Of the meteors by a serial num-
Der and the time recorded.
A year ago the Harvard Observatory asked
for the cooperation Of observers all over the
world-not only astronomers. but intenigens
laytnen evsrywhsre-and q full circular OF rules
TO govern such observers was sent out by the
university. The most important part OF the
circular v - follows:
The most important time for observation
Il from midnight until dawn. as comparatively
few mstsors are expected earlier. Observa-
tons are particularly needed at hours when
they cannot be made at the ohssrvatories OF
Europe and America. In general. the tmo
required for ten OF more meteors 10 appear
In the region covered by the accompanying
map should be recorded. This observation
should be repeated every hour or hall hour.
IL the mstsors are too numerous to count All
those appearing upon the map. the observer
should connne his attention exclusively to
some small region. such as that included be-
tween the stars Mu ursas Majoris, 40 Lynois.
and Delta and Alpha Leonls. II the meteors
occur but seldom. one every FIVE minutes. for
instance. the time and class OF each meteor
should be recorded. Also note the time during
which the sky was watched and no meteors
seen. and the time during which that portion
Of the sky was obscured by clouds. Passing
clouds or haze. during the time OF observations
should also be recorded. The date should be
the astronomical day, beginning at noon that
Is. the date Of early morning observations
should be that OF the preceding evening. Spe-
city what time Is used. as Greenwich. Standard
or local time. When a meteor bursts. make
a second observation 81 II. light md color,
and, when it leaves n trail. record the motion
Of the latter by chartinE the neighboring stars,
and sketching tts position among them at short
intervals until IL disappears. noting the time
Of each observation. II the path ~ a meteor
Is surely curved. record it fully on the map.
photography may be taken. first. by leaving
the camera at rest. WREN tho images Of the
starr will trail over the plate and appear az
lines: or. secondly. attaching the camera TO
an equatorial telescope moved by clockwork.
when a chart Of the sky will be formed In which
the stars will appear as points. A rarid-recti-
linear lens Is to be preferred In the first case.
a wide-angle lens In the second. The fun
aperture should be used, and as large a plate
rs can be covered. The most rapid plates
are best for this work; they should be changed
once nm hour. and the EJECT times q starting
and stopping recorded Care should be taken
10 stifen the camera by braces. 20 that the
focus will not be changed when the instrll-
mcnt is pointed to different portions Of tho
sky. especially II the lens Is heavy. II the
first method is employed the position OF the
camera should be changed after each plate.
so as to include ms much a. possible Of the
region OF the map on each photograph. IL
pointed a little southeast Of Epsilon Ieonis.
the radiant will reach the centre Of the field
about the middle Of the exposure. A watch
q the region should also be kept. and tho
exact time Of appearance and Iath Of each
meteor ss bright as the Pole star should he
recorded The plates should be numbered
90 the Elm side with n pencil. and should be
sent TO this observatory with ACCOMPANYING
notes and other Ohse rvations. After measure
ment here they will be returned II desired.
The value Of the results will be much increased
IL similar photographs can be obtained by a
second camera from ten to forty miles distant.
and preferably north or south 81 the other"
Amateur cbser vsrs Interested in watching
.he meteors may find tho constellation Of the
Lion readily by taking the Great nipper as
A starting point. 1t will be remembered that
the two outside stars OF the bowl Of the dippor
are used for pointers to the Pole Star, Take
the other two stars II the bowl as pointers,
In the opposite direction. TIL a large first mag
nitude star IA reached. about ten times the dis
lance between the two pointers, This star
will be- found to be at the end Of the handle Of
a rather close representation ~ a sickle. which
is the most obvious pictorial character 81 Leo,
Tho radiant Of the meteors is a little north Of
the centre Of the sickle. The paths Of the me-
taors will appear shorter as one approaches
the radiant. those close to the point being little
more than flashes OF light. They then pro-
Gressively lengthen. till neteors half the arc
OF thu visible sky away will almost enc!rcls
the hea yens