The sun. [volume] (New York [N.Y.]) 1833-1916, 1897-02-21
NOTES ON SCIENCE AND IND UsrRy.

that universe has after all fairly well defined
limit Tho nrst OF these conclusions Prof. Newcomb
bases an idea that the which are called the
smaller ones. because they less bright may not
be large stars at very great distance. but perhaps
smaller or DINNER ones nesrer.at hand. The old
idea Is familiar to all. namely. that all the .tars
OF the brightness. and that the fainter ones
very much greater distance from than the
bright ones; this theory. however. has boer -N~ak
ened by later discoveries. such as, for Example.
| that Sirius has companion whose light. n equal
surfaces b. considered is but fraction OF that OF
its principal; ana astronomers have come TO recog
nize din stars. even dark ones, like the com.
panions Of Aigoi, about which much has lately
been written, to bn quite As common. perhaps. in
tho universe tho bright ones. Prof. Newcomb's
proposition as to the limits Of the universe regard
ed more novel aud striking suggesting rs IL
does. the possibility that some day all the stars
will be seen.
Two ingenious improvements have recently been
brought to notice in the construction Of machines
for puv erixing The peculiarly in this
| consi,ts IN having two puivcrizing cylinders ar
| ranged eonceDtrtcaiy within the other. capa
| bic Of being revoived rapidly in opposite direc
tions the rate of speed of the inner cylinder ex
cecding that OF the outer. The latter 10 also pro-
vied with q series OF inwardiy extending teeth, the
| inner cylinder having outwsrdly projecting
series capable of passing between tho teeth OF the
other cylinder, the ends OF these teeth extending
close to the walls Of the cylinders thus forming an
shnu'ar space between 'h' walls. siowD re-
! 'o''inR ieeoihs ao''cs eohuuc'' 'no orc from
stationary hopper into tho front end portion OF tho
abnuiar space. where It IL acted upon by the rap.
Idly moving teeth. subJecting the ore TO . contin-
uous series OF hammer like blows. which break Il
up; It 10 still further reduced by the succeed
| - a., 80 g.. - -. -, =,
| ,.,, -, IT,. .,,s.. a., - -,
| -. =, e.. c,.,, =, ,.",,
|
|
Engineers nav" po'ntod out 70 builders OF ma
| csinery. /" an essential fict to be borne In mind.
mat additionai size IN part OF an engine or ma
ohine TOOL DOCS NOS oy any means necessarily imply
corresponding increase IN nr"nEth-thas Is, tho
same metai may nave strength or say $4,000
pounds per square inch In large sbaft. 10000
| POUNDS when dra~n into one'inch rod ana ioo.-
ooo pounds 10 the FORM OF wire the variation being
que 10 the manipulation which u mas undergone In
H. Thurston cites tho case OF q designer Of rock
drills who was continually eniarging the size and
| increasing tho number of his cylinder hcad bolts,
| which as steadily continued breaking under tho
| blows OF the piston. He learned nnaiIy, however,
| TO lengthen the body of the bolt ana reduce its
! diameter below that of the bottom of its threads
| and 70 understand that strength without estensi.
biiity In such pisces mean. Inevitable fracture
under impact. Tlus where an exceptionally large
rod or heavy crank IL found, 10 10 often the case
| that the last OF that pattern broke through some
accident the designer then making the next itt,i.
| larger that Il may stand In the same contingency
when very likely the failure had no relation to the
| prvportionI OF tho mart or Of the engine,
|
7, q. found .h., IN. .dd,,,o, =, . x.,x .,,us, .
| ,,v y, rho.,no,n. % 81. o,,.. ....,,,.,.s.-,
| h,o,,o ,,od,... ,r.., .h.,... =, ,s ,,,
| ,r.,.,,,Iir ,n.r...,n. ~. ,,,.,.,, 80, ,,.,,,,,
| Ca .uox q, n,o,,.., -, ,,.-.a,,..,,.. =, -,
|
n, COMM, and 80 a, m. ,o,,o,,,o, -, -, ..
I'm, tho .mount n, ,ho.n,o,,. ,.r,.. ,r ,,,...,
| ,r,,,,,., AZ, ~. v., to-, n, .. n q = -. >,
| IN. n,o..,. =, r,.ru-..,,,,u. ,,.,,a 90, =
:. .ar.a % .onn.,". n,o.... 49, -, p"o'paou.
| =. .o,,.., - a.. .....,,,.. =, -, -,
a., Iii. -, r.. -. o., ....s, -.
nso,r. 4. 49, ,n,r,,. ~. ,.a.,,. =, -. -
-, ,.a... a. 60. ..~..,..u o. = -
-. TO-, WAS
II 10 considered by authoritie. whose experiments
and proonsef investigations cnti,ie their opinion.
to much weight, that light whi.h 1, more than
normally rich in violet and ultra violet rays Is in
furious to the eyes contributing In time to A mar.
tial destruction of the nbres OF the crystAln, len.
and, wheI excessive producing erythema and
symptoms resembling those OF sunstroke-wort.
men I'm electric iirht works. ~ frrouen,,y ,.no.ed
to powerful arc lights being afreced in this vay
IL f. mt desirable however that the light should
he too rich in yellow rays q. these temporarily de-
stroy the erythrosin or photo .enst,v. .ub,t.nc,
of the rctina producing great fatigue OF the nerve.
consequently requiring darkness for its formation
and the restoration OF normal visio. Though th,.
destruction and reformation constitute a natural
accompaniment Of tho ordinary exercise of 1,vht
yet as the yellow rays are moot active IL 1, con.
siiered advisable that they should not he I'm "a.
perts in this line. TO which attention has been
drawn by Prof. crooEes. Is that the best form Of
artificial light Is ono containing little ultra
violet rays. No excess OF yellow rays and just
ctent red light to communicate warm. pleasant
tone 10 objects around.
Reviewing the various attempts which have been
made In the past to realize an adequate method Of
nreproof construction. writer IN the Engineering
Magazine declares that so ineficent In results have
| been these attempts that of led