The sun. [volume] (New York [N.Y.]) 1833-1916, 1897-06-13
NorEs ON scIrvoE AND 1xDUs1nr.

finss, under certain circumstances, II discussed
thoroughly by a correspondent of the Couterv En-.
gfneer who has made n practical study OF their
workings. He smphaucaiiy combats the idea that
q gas engine IL a. ennoient and cheap AZ q steam en-
Rino At coal mines, where fuel u cheap ana power
need not be conveyed long distances under Eroundi
but even at many coal mines there are points In the
workings where pumping and hauiago must DO done
mechanically, and, while the amount OF coal avail.
able is considerable. IL IL not large enough TO war;
rant tho installation OF either steam, com pressed air,
or electric machinery, even II the use OF steam Is
practical. In summing up tho different cases In
which gas engine service will be found both eco.
nomic.i and efficient this writer specifics the follow
invt For hosting, hauling, and pumping from dip
workings distant from the main openings; also for
Running isolated ventiiating machinery, az well as
for Isolated pumps 20 supply watcr at mines not
equipped with electrical plants and where the in.
s~taliation of a plant would not DO eIpedient.
Woven paper Is = new article invented by W. A.
MauTain, q Providence, n. l., manufacturer, which
Is designed N an improved kind OF lining Tor car
pets. A novel description Of loom is employed In
its production, and into this loom strips of the pa.
per . yard long are fed automatically through q
tubular guide. which folds them lengthwise; these
strips form q firm yet elastic weft q quarter of an
Inch thick and securely bound by warp threads.
From the loom the woven roll Is taken to q ma.
chine which gums and stitches on the paper selvnge
and reinforcing strips Of Taper. In another
grade the lining, as II comes from the loom. 10 in.
closed in paper. which, when worn away by use,
leaves tho interior intact. Tho niling uoes not nd.
hero to the carpet. Its thickness Gives an elastic
feeling to the carpet. and the loom insurcs = uni.
form product.
An account OF much interest II given In the Leip-
sfocr MonatsohrUt FUR Te1tii Industrfcn OF certain
comparative experiments made in tho working up
OF FAX retted by what 10 known as the Baur method
and by the ordinary water process. Some of this
max was grown at Cframschuetz. In Lower silesia,
and the remainder At Popeiau. one.thlrd OF the for.
mer being sent TO Popolau TO DO rettod in the usual
manner. and tho other two third retained and ret.
ted by the Baur process; one.haif was afterward
worked up by hand in the Belgian style at Popclau,
tho remainder being for treatment by machinery at
home-a portion OF the Popeisu fax being also ret
ted BY the Baur method, and subsequently worked
up by hand. In comparing results with the raw
material at the spinning works 10 was found that
the nore from Popeiau waa nner and longer than
that from CiramsonuetE. Ths materials treated by
the Baur method did not exhibit the nne glossy ap.
pearanoo characteristic OF this process, neither
were they 20 long in the nbre a. those rettsd in
water. As regards yield Of hacked max, the snm-
pies dressed By nachinery gave o7h 70 6th per
cent. Of long hbres. an unusually high percentage
and one approaching the ,ieid OF Dutch and Bel.
CLAN max, whereas those Creased by hand labor
yielded 53 TO 60 per cent.
The fact 70 familiar to those engaged In the differ.
ont lines Of Industrial chemistry and therefore feel.
ing the need OF terminals that are inexpensive and
permanent. that gas carbon Is not available In large
sheets. such 90 are commercially required. and
hence those have been made OF powdered coke,
baked with . cemantng material in the Same man.
ner Is in the case of electric light carbons. Such
carbon plates, however. are not permanent, but
soon become disintegrated by tho action of the 30.
buttons. and especially by the action OF tho nber.
ated gases. Now. according to the claims of DR..
Albert leasing, put forth In the Electro chemische
zeitschrUt, this problem he has solved by produc.
ing carbon sheets entirely Homogeneous and free
from cracks. by q fusing process which not only
insures the permanence OF tho sheet. but also In.
creases its oonduetivity. This new product Is
claimed to be harder than steel. readily scratches
glass. and is proof against the emery wheel.
The immense amount of study aud time applied by
Ambrose swasey TO the construction OF an engine
OF perfect precision for graduating the .'circles' of
q telescope has been rewarded. Casters Magazine
asserts, by the production OF u dividing engine un.
surpassed for accurate measurements. This. con.
aidertng tao difficulties involved In the case OF such
engines. Is scientifically noteworthy. Thus. a. one.
third OF an inch subtenda an angie Of one second OF
arc at n distance of ono mile, IL Is manifest how mi.
mute must be the measurements on the periphery of
4 circle. say, OF three feet diameter, and, as there
are ,e96. 900 seconds OF arc In q circle, and As all
seconds must Theoretically have the same value,
the difficulties of dividing = circle In which the err.
rors snail be less than . second OF arc are obvious.
Homogsneity of material. proportionate parts that
will equally respond TO slight changes OF tempera-
turc. and various other factors enter into this DIFF.
ncult problem. aside from the nnal corrections OF
the dividing mechanism. Every approach 10 per-
fectioa. therefore. be it never attained absolutely,
brings greater assurance to the astronomer Of the
accuracy OF his measurements
A recently constructed reservoir in Pawtucket.
r. l., exhibits ONE novel resorts OF . practical ma
turs In engineering worthy OF note. The plan of
this reservoir, TO meet the hilly area, is circular.
with an inside bottom diameter OF 95 feet. q top
diameter of 81 feet. and a depth of lie feet. The
concrete used in the construction OF the bottom and
walls was composed OF one part Portland cement.
three parts sand. and six parts gravel. and the bot
tom was OF concrete nine inches thick over the
whole area. excepting ut the walls. where 1t was in.
creased to one foot nine inches thick: there was no
joint or line of junction between the bottom and
the walls, both being laid simultaneously as one
mass. The concrete OF the reservoir walls 10 four
feet thick at the bottom and TWO feet at the top. tho
height being twelve feet. with an inside and an
outside batter OF an inch to the foot; Embedded in
the concrete walls and extending around them are
four rings OF wrought iron OF V to u inch diameter.
the nrst of these being one foot down from the top
OF the wall and n foot from the back. the otherB
ono foot apart below this. outside the concrete
walls and extending around them is an earthen ON.
bankmcn: sioped from the top OF the wall: inside.
the concrete bottom was covered with cement plas.
ter. and finally tho walls and bottom layered with
hot Trinidad asphalt.
The proposed mammoth geographical globe to DO
constructed for the Paris Exposition of 1900. &C.
,ordinR to the plan at present contemplated will 10
not iess than 400 metres In diameter. whilo that of
the exposition OF 1880 was only about forty two
feet diameter. ono. mlllloQtl that of tho earth
Again. the difference between the two. a. explained
and illustrated In La Revue. shows tho features of
tho contemplated structure to bn far more wonder.
full than those OF the former. 1t is to contain upon
It's ave interior floors representations OF all the
various countries III the world. That is, the visitor
Is to be TRANSPORTED by electric railways from one
country TO another In such q manner that. in ira.
verslng the interior OF this huge globe. ne will prac.
ticaliy visit overy Part of tho earth.