The sun. [volume] (New York [N.Y.]) 1833-1916, 1861-03-11
Scientific Items.

PROTECTING THK BsTroM or SHIrs.-A
composition for protecting the bo,tsm Of Ships and
sher structures of iron, hss lately been patented IN
England. The manufacturers Of this new article
use barnt clay, lghsrgs, white lead zinc white,
sharp SEA or river sand, or cscincd Hint, tar, or
btumep, and arsenic. All these materials are
ground together, linseed ether suitable oil is
added, and the whole is exposed to hea, OF sbou,
two hundred and ten degrees In some cases the
oil IL dispensed with, aud . greater quantity Of
bitumen used. Ansr the composition has bsen
heated sufficiently, naphsha or other spirit shen
addsd, and this Is applied In warm state 70 the
bottom Of the iron ship or oshsr ssrussurs TO b
protected. The value Of the composisios does nos
depend on sny precise proportions Of TIE several
ingredients Of which IL is msde though the follow
ing u found the most suitable Ten parts OF the
bun clay, eight parts OF ithArge, forty parts OF
white lead or zinc white, four parts Of sand or
int four Of tar or bitusen, and two parts asenic
In some cases, two parts OF sulphste of zinc are
ADDED, and, II IL DO des red TO give the composition
. good color, five parts ot venetian red added.
ArPARATus FOR PuRiFyISG WATER. The
London Times says tha, water impreyusted with
lead may 10 made wholesome in an easy maunsr,
viz, by means Of well burnt anissl charcoal,
ing Recommended by Dr. F,RApAY-thu Is, by
string upt Ito ucool Ia the water aud allow ing
II TO sub-ids, or ly l,tering in the water through
q W s1cl containing the charcoal In po wdsr.
An apparatus In q very portable form has bsea
recently invsn,ei for the purpose OF applying char
CO al 10 the pur c tion Of water from both e,d and
o~gauic matter, AID the te.ts which have been
made show ths apparatus - be remark, ably we'll
adapted " the purpose. 'C.n easily bs attached
" the supply pip, of cisterl, and thus used ~
the time Of craving the water. the composition
thus used ss purifying medium iss mixture OF
animal charcos silica, and iron. ard although ills
suf6el.Itly porous to permit Of water passing
through as rapidly as Wy any known method Of
hl,rsiop, IL does not allow Of the i'm pursies psns-
,ratLg below lis extreme surface, ON which they
CT n be removed II, suy time by means Of brush
or cloth. The 10 ijhy aud ihdeasruc,I lity Of
Tits purifying medium are 8, great, II Is c'.inod,
rs 10 ievsnt any liablty Of deterioration or get
ting out of order.
MACHINERY FOR MANUFACTURING PAPER.
The ordinary construction and arrangement o.
machines for shs manufacture Of paper, familiar
to all. An Improve nent, however, has b:en slt I.
ed by which Just prior to the pulp leaving the wire
/ web, . very ingenious rsDgoment 10 made in .hs
machine, with view more perfectly " extract the
Il WATER IL consists OF a metal box placed under the
L trayeip web, and comm unicAsing with three pow
l eriu' ai.pumps These pump, are sci In mo.ion
ny the steam cugiue, and produce powerful es,
l hsH,t vacuum In Ihe b.x. Tae sdsct uC ths OF
-, SUI trucumbt layer of pulp is 70 suck In 'h,
s,er. and 10 cause thu fore, very completely "
i ttrlace one with Ano,ler The hrnnsss Of ths
H,ure ofthe paper il thus materially promoted.
| The paper now passes between two rollers upOr
web Of felt, leaving the web upon which II wa
i reduced, which Te,utns for q continual fresh sup
py, These rollers ale covered with felt, Ant
Guezs out sonsidsrable quantity Of water, an
the paper now becomes pretty firm. II Is, ho "
ever still wet and uoht for any useful purpose, an
u Is therefore carried on between other rOllsrs
which give 1t additional pressure.
Bu, no amount of force which could 10 ererted b
Cylinf ers, wsuld b. capable Of entirely removing
the waite, and rendering the paper dry and firm
An additional orce is therefore 0Nough, into requi
ton, In order TO accomplish ihe dssired end Th'
damp but tolei ably smooth sheet Is received by I
lsrse cyliIder revolving on its axis. but charged
with high pressure steam. The heat thus oommu
nica,ed dissipates the moisture a. steam, and the
psp.r becomes rapidly very nearly dry. Ia order,
i row,yer 70 complete IT, 10 passes over several Other
Il cyli.d.rs similarly heated, and hlAlly smsrgsi
1 rcm the last Of the series . beautifully white
/ sno uth and c1niiI Iuous sheet.