The sun., 1901-11-10

4 long series Of experiments on under
ground temperatures ha, lately been printed.
In general. but not always, the highest tenn
peraturcs were found at the greatest depths.
Temperatures taken az different parts OF tho
same statum AT the same level, sometimes
differed degrees G The air temperature
at any level il usually lower than the rock
temperature, the difference being occasion
ally 10 or IL degrees. Sometimes the air
temperature has been found 20 be degrees
higher than the corresponding rock tenn
perature. The highest temperature OBJ
served was 90 degrees c AZ 077 meters, but this
may have been due to local causes. The
highest air temperature was 13i degrees
at 77e meters. The layer having AN invaria,,
BILE temperature OF degrees { was situated
at rs metres below the surface. Determiia-
ton of tho depth corresponding 10 an ia,
crease Of temperaturc OF | degree Varea
100 metres this depth varied from IS to ?s metres.
200 m etreS this depth varied from u to 81 metres.
80 metres ,his dsp;h varied from to 20 meires' sir
500 metres this depth varied from 20 70 o. metres,
eo9 mcre. ,his dsp,h Varied from to ms,res'
700 metres. this depth varied from "a to no metres.
II averages arc taken this depth is found
20 be for each 100 metros. Less thah 100,
% metres: than 200. ~ metres: than 900. ?s
metres than 400, n mette.. than apn, ~
metres than ooo - metres than 200, 2s metres.
In a general way IL may be said that each
Increase of depth of - metres corresponds
TO an increase OF l degree IN temp erature,
THE pPIoHrNfss OF STARLIGHT.
Mr. Gone has lately in quired: What Is the
relation Of the total light OF the stars 10 full
moonlight lie proceeds as follows The
brightness Of q star Of the third magnitude is
5I2 times that OF the fourth. OF \ star Of tho
18th. 2 5l2 times that OF a star Of the tN.D
and 50 on, So far So good. lie assumes
that a formula given by Or Gould for a lim-
tied number Of classes Of stars holds Tor all
stars visible in even the greatest telescope"
The assumption Is erroneous not to say alb
surd Proceeding In this way he calculates
the number of stars Of different magnltudes
as follows
stars 10 the iOth magnitude Inclusive: sa rs
stars to the 18th magnitude Inclusive. Sel gD
stars TO the i7th magnitude inclusive. u so Ht.'."
He next assumes that the number OF stars
nitude Is 100. .Ooo.ooo. This Is the crudest pos
sible estimate i was, made before photo
graphic charts of the sky had beon secured,
and takes no account OF the enumeratlons
hireaoy n'h n,a1e on d,rn he fnTsy"ing taiIe
40 as to reduce II ,Nn.op,O0 20 l1 WOWp
and all other numbers proportohaly hnd
stars from 50 70 s,5 magnitude; se,o
star, from ~ to 1917 magnitude 1000 1U
s. s.r. from from ' 30 70 * nssaad: %ssaad: ,SS ;% 90
lie further assumes the lco 600 nebuls
Co -hue with the hrlllaucy pf an equal num-
Der Of eighth maznitud" stars and takes
sirius. aud Gls,DOO times u- brght the
moon. hs'ng mar,hslled the" data, some
exact. some pretty exact aud some quite
doubtful. he concludes
.. Total starlight 100 fllI tnoonllsht
centazc Of error for IA. reasons stated
An sppro vimatipn of II ht- ,ons ld.ra bic
Interest and i quoted for that reason
THk ooAi-I,E rEaprrrs INDUSTRY.
At the GlasgDW meeting Of the B A 4 :
statistic on this Industry dulng the last
.iteen year. Yer" pre'sa'e'i l,e mAAnu-
land The export u 'n1..'ar color, from
uermaIy tehgiusiyc ~ ahlniin",. "as
isg4 the value 81 her EXPORT Of these tHluFs