New-York tribune., 1878-03-30
SCIENCE FOR THE PEOPLE.


ard holders read last FAN by James sonervile before
the American Gasght Association 1t points out very
clearly that glass shades most used fer gas are so
unscentincay constructed that they absorb great
deal OF light This is especially the with globes
that have contracted aperture at The bottom III IL
recommended that this aperture be never less than four
inches Computations Of the loss OF light by shades OF
different kinds have been brought together by Professor
Chandler and are presented in this pamphlet The low.
absorption OF ground glass Is nearly 80 per cent
there Is only specimen at this low ngue the oter
shades Of that kind absorbing more than 81 per cent
Opal glass Of SO TO 80 per cent; green pur-
ple and ruby glass. 81 TO 80 per cent IAN tis
parency, over 97l2. The pamphlet mentions a pan
adopted by gas company In Indiana. which has given
great saisfact on to consumers The company Iurnlshes
burners, with the gas and has found 1t economical TO
provide them dcreBt sizes for the various rooms IN
house. 1t may here mentioned that the latter oD,
jeet has been attained IN THE IRiBUNEs composing ana
editorial rooms by the OF q burner which contains an
Of contracting the How OF gas Dy srciem
and shades with wide bottom aperures have also oeeh
adopted the result be'g better light at reduced cost
CRUsTACEANs IN DRINKING WATER.-Obser-
vatlons made OH the water of Lake Erie at Cleveland
show the presence OF numerous microscopic animals
They are all OF kind possibly species of cyclops
They are abundant both in Summer and Winter but wheh
the temperature Is below 800 the females do not hach
their eggs. The duration OF individual life among te
does not apparently exceed month. but In tho c
to forty eggs apiece The Cleveland people do not now
ever, hesitate about drinking the lake water since .ne
trio iucc contains, death to these animals
SEA ISLAND COTTON.-ln lecture before the
South Carolina Historical Society," the Rev. Dr. C. G.
Pnckney gave details rs to the present CONDITION
of the sea islands OF our coast famous for
the production Of long hbre cotton. Comparatively lew
white people upon the islands. The negro popu-
lation inclined be rftless, and cotton culture Is
not conducted with the former skill aud success or
fifty adults on Pnckncy Islam only two are prosper
ing From eighty TO ninety bales of cotton
were produced there, per acre, before the war;
now. twenty bales may BE- accounted fair av-
erare The income from that island formerly
100000 wear; az present 1t barely clears It's taxes.
The population of Beaufort County in 1850 was 10000
In 1879 43 OO0 but the number OF under cuTa-
ton has diminished by twOthrds, and the profnct OF
has fallen off nearly half OF cotton more than
hall; % potatoes nine-cnths. Dr. PncKncy thinks that
the negroes are for part rerogadng In their
social condition. though there are many Instances OF i'm
provcmcnt among them. A committee Which was ai-
pointed BY the Agricultural society OF south Carolina Ns
recently reported gct on Tor restoring The prosperity
coast lands OF the state The report Is elaborate
and urges rotation Of crop. Instead of reliance on nee
aud cotton. II recommends that the c0w-ita be cult
waited, not FOR food, but TO be used feTthZer with
the addition of mar and material from The neighboriu
phosphate beds Bermuda grass IA regarded - most
suitable for nitivaion In that region to rfodnce nay
Oats have been planted there for several years WIN hr
advantage and experiments IN raising wheat begun III
1876, are regarded aS successful
LIONS AS IE1-.-h ltltFI II NubiiNll'u
Forest and Stream from MrsM Lincoln, o' No. "a How
nfd-st. Boston, concerning "A hon aud honess domest
Gated In her house She writes that She aumals were
born IN this city the Summer of 1870; she has had
charge OF them since then and IN their earlier days fed
them from a chd's nursery-bottlc. The male lion Is
estimated weighing $50 pounds and Is OF the rare
variety that 10 distinguished by black manc. Both
ANIMALS described as Ia fine condition; they are
gentle and anctonae 10 their owner. aud love to be
petted by her. They had formerly tie range Of the
whole house rad the garden but atterly the Boston
police n'criere ana nnIro|cd thef lia5,'is 10 2l,e
Of iayortes by Women the exclusion OF 81 Kinds o AMI
nal pets from the W0mrn's Home In this city ms less
arbitrary. Chaurcr In the Canterbury Tles, a udes 10
the o. tame lions, probably rerievcrs for the plr
poses Of the chase. But 1t has not been suggested thn
the Boston lady Is preparing for the part Oh Mrs Leo
Hunter
THE ELECTRIC LIGHT IN PARIs.-The cx
pertinent OF lighting Place de Opera by the Jab
ochkof electric candles Is regarded success nnd IL
TO be kept IN permanently Other squares and public
places will soon be similarly lighted. The invention Is
I'm use in several large establishments in Paris and has
been employed a-o in facilitating the rapid construc
ton building. There is 10 doubt that illumiua
ton by electricity will he brilliant feature oi ne iEei
national Exhibition aud that the giOunds VIII be thus
lighted on festival nights.
A CITY SLIDING DOwN.--A change of level
and position IL going at virginia CITY, Nevada. which
may worth the study OF experts IN seismoogy The
whole locality been DulfOWcd Dy tue SILVER
mines As a consequence the entire town is slowly de-
scending the face OF the mountain on which II
rests The movement is so uniform and gradual not
TO be noticed on surface. water main recently
covered street crossing was found to be icescoped
for the space OF foot and also 20 bent that two
feet Of IL had be replaced In another part Of the
town the underground pipes found TO lie crOwding
toward zach other long crack has been traced IN the
ground the western side OF the town. ABOUT egat
aiout
opa Hotel Is said 10 have moved i've Inches since II "ns
bnt The inhabitants regard these facts with an equa-
nlmty that would he impossible in more settled cOnmu-
nties aud take the chances of an earthquake with APP
parent indifference.
THE COMPANION OF SRiUs.-In a communI
cation TO Chicago Tribune, Professor W. Burnham
that his experience accords with that of Pro-
fessor Asaph Hall to the facility with which the com
panon Of Sirius be observed with Instrument OF
high power The oycrpowerDg light OF the large star
makes tho companion difficult to perceive with small
aperture. except by gmpscs and under very favorable
condIons Professor Burnham has however, repeatedly
seen IL with n six-nch telescope Hc donbts whether
authentic accounts of ITS having been seen
with smaller aperture. lie prOnOunces the report hat
othor companions 10 sirius had been discovered rs IN
Trustworthy erroneous. similar verdict Is passed
tho alleged observation Of two satellites OF the Pole
star nearer 10 IL than the Uerschc companion. Such
mistakes are due 10 false images or Imperfect adjust
of the telescopes used. aud in general have oc-
CURED with inexperienced observers though reputable
astronomers have been sometimes thus mlsed
ANALYSIS OF ADELTERATED BUTTER.-The
City Chemist OF Cleveland Dr. Caassen IN recent re-
port on butter aduerated by mixture with lard. gives
spc method Of testing for this fraud The suspected
butter melted and about fifty grains OF II poured into
test tube when this is cooled to the temperature OF
the human hand there Is TO be added mixing slowly by
agitation 800 grains pure sulphurc acid II the butter
ia pure the mi xture will at become yellow, and af
terward bright yellowish red. II lard is present, the
mixture Will pass from the color last named, 20 DrOwnsh
red brown. and. perhaps brOwnsh black InIneric or
annatO is frequently used 10 color adulterated butter
TO detect either Of these dyes the butter should be
ted and shaken with twice the quantity Of alcohol
The butter having subsidized the Dye, II any Ia pres
emit Will appear above, ia solution in the alcohol, and
tint II yellow; but from pure butter, no color wli be
tract,d.