The sun. [volume] (New York [N.Y.]) 1833-1916, 1894-10-07
NorEs ON SCIENCE AND INDUSTRY.

The opinion has recently been expressed by
scientific writer that some information as 10 th'
degree Of perfection characteriziDg the eyet
retroactive system, and a. TO the ultra-micro
scopic structure Of the retIna cones, might per
haps be derived from comparison Of the small
est intensity Of light that can be perceived
under different conditions. the fact being In
stanced that the light Of a star which IL just
visible hiss been shown 10 be equal 10 that OF .
candle at a distance Of some twenty-seven thou
sand and Eve hundred feet. and here. II IL a.
serted, the source Of light may be taken 70 be .
point OF absolutely inanpreolable dimensions.
On the other hand. NJ. Aubert Il quoted as declar.
ca be enf one of the SrsSt
ness Of the surface Of the moon. The opticien
n' o . e s' aaS
total light distributed over this area VIII be
candle at aos feet, and the light received by
tSon n SDG and iwentyS part Ss of tss that
OF candle AT only $3.50 feet. For point
which K not Of ID Rs s%e.t
appreciabe intensity of light, or II Ia go II the
retlnsl cones be assumed 20 act Independently OF
one another In perception.
A practical and convenient apparatus has been
devised BY which much of the labor and trouble
involved In the mixing Of cement IL saved. ~
consists of q substantial bowl OF cast brsss lifted
with cross arms, easily removable, which fur
nish bearing for q centre crank shaft The
hand crank when rotated transmits its motion
TO . short crank in the bowl. This crank carries
paddle which circles in the material In the
bowl, and. at the same time pinion on top Of the
paddle shaft engages with fixed annular gear,
which causes the paddle TO rotate on it, axis,
the combined movements thus given 70 the pad
die mixer producing thorough distribution :!
all parts Of the contents: An advantage q
entirely OF brass, except the hand crank. out
side When ready TO empty the bowl. All the
working parts can be removed In q momensby
drawing out couple Of pins.
The pumping Of coal TO market. by crushing
the stun and mixing It with water. Ia now being
discussed In the scientific journals as = pFacti-
cable method, and IL IL suggested that not
merely the vast heaps Of culm which are now
going to waste in the mining regions. but, in
fact, the whole output OF the mines. might thus
be sent 10 the consumer, the great recommended
ton Of the plan being It's commonplace is, coal
could be. pumped 70 market" II In declared, for
onetenth the cost Of rail transportation, II there
such system o nsmels tSa. Il %epaia b
pDIsS sSGa e% TSss sss Of
dust for from three TO nye cents > ton, and
purities for i've cents more, this latter process
also leaving II in q greatly Improved condition
pared the plan Is TO minsie the material with its
pipes as 8 practised with oil. 1t Is assumed that
and but little heavier than water. would re.
main in suspension easily, absence Of grit would
could SIs'H Re from the oo. By
soaking Moist coal. when exposed TO the air.
rapidly and Is liable 70
water in settling basins these drawbacks would
not be experiepced; Il not to be used at once,
up again before pumping TO consumers.
In a paper read before one Of the mining insti-
tutes Of England, Mr.. Wynne. o noted authority
In engineering practice, presented the subject
from different standpoints-of the most ap-
proved system Of underground haulage In coll
iories the cost Of which is. Of course. one Of the
most important items In the production OF coal.
and the use of animal locomotion is, except for
short distances. an out-of-date method. Having
discussed the advantages and disadvantages Of
pressed air as, unquestionably. a convenient
FORM in which to transmit power from the sur
pumping. heading BY machine, drilling hoies for
blasting. and driving coal-cutting apparatus,
and. with It's convenience: may also be combined
10 roads by heat or leakage pertaining 10 steam.
As compared with steam. compressed air Is
distances underground, but this
has It's limits looking at the increase IN the rze
u pines 70 ga carry the air extremely long dis.
% the compressor to attain the required pres
'ure; then. too. the exhaust from the motors
,dding little to its volume. whereas steam has
he opposite effect on the temperature, and de-
nands special means for It's disposal.
A combination process for treating gold and
Overwhelming ore Is coming extensively into
ise-desgned especially for the treatment Of
ores carrying gold and silver associ-
ited with the inferior metals such as iron and
copper pyrites. lead. zinc. anthony. &c. In tho
Machine or mill designed for this purpose the
ire is fret passed through q rock breaker or
rusher into ore bins, passing then automatieal-
nto the mortars OF battery, where II Is crushed
vet and ischarged through the battery screens |
eEs sss sSs Pass which the
re; from these plates 1t passes on TO |
he first set OF concentrators, where the |
leayier base metals are eliminated, The tail |
ngs from these machines then pass on 70 the |
econd set OF COMMENTATORS, where Anal concen- |
nony &c; and the tailings from this last set OF |
a ma an CONTAINING the sIphides ehiorides
urplus water Is drawn from the pulp, It Is show
lied into the pans, amalgamated, discharged
orted, and melted In the usual manner.
A recent process is reported for the purihca-
lon OF beet juices with an iron chloride which
said to be satisfactory in It's results, It being
laimed. In fact, that snch publication is more
omplete than Is possible TO obtain with limo
nd the regular method OF carbonAtation; the
Horde used also precipitates the albumen, and
ther organic substances arc likewise precipi-
ated at the same time. In this process, raw
NTH their aFsiiniy Z about oSs p per csn %s
nd TO thirty gallons OF Juice 10 added one
uart Of iron chloride. lime being then mixed
J and heated 20 one hundred and seventy
z degrees; second oarbOnatatiOn follows, and
, twenty Ave gallons OF Juice one-hAif pint OF
horde; the saturstion that follows should
urihcatlon IL properly done. there remains no
ace Of Iron, Another interesting method do
ribbed In this connection Is that Tor the manu-
.cture Of levulose with beet molAssss. In this
Ase the saechArose Il nrst transformed into
,ere win be formed = pIeSlpitSts Of leyulOsats
Iher substances remain In the solution, BY 8 |
areful nltrationAnd eAEbonAtatton Il bsing pos
BILE 70 obtain pure lsvulOse.