The southern sentinel. (Winnfield, La.) 1883-1910, 1884-12-05
Timber and Tools.

Timber and Tools.
1t is fact well known to mill men
that it is not always the harder woods,
in the ordinary acceptatlon of the term,
that are the most wearing to the saws.
Many practical persons marvel at this
and wonder to themselves why piece
of timber showing small crushing ten
sion and other strengths, re iuires
more power to work into lumber, and
at the same time wears out the saws
and cutting tools faster than other va
rieties of timber, the strength of which.
| in most respects, is greater.
A log of black walnut and one of
| burr oak of the same sized worked into
the same sized stuff will show widely
different results on both saws and ma
| chinery. LII we attempt 10 rive or split
these logs the walnut will work much
easier than the oak. and SO far as the
various strengths are concerned the
oak is superior by far, but when cut
| into by tools of any description the
walnut will present much greater re-
sistance than the oak, and the same Is
| true as regards many other varieties of
hard and soft timber.
Ii we take longitudinal section Of
these comparatively soft timbers which
are SO hard on the cutting edges, we
will find the minute pores or interstices
filed with minute glistening particles
or CRYSTALS, and sub. ect TO chemical
analysis we will find them composed of
silica, one of the very hardest minerals
known, while with the hard. casy-work-
ing woods they will be found nearly or
quite absent by both the microscope
and analysis. these lutte particles, so
timely divided rs to be lnsusceptible of
ordinary touch, are really better grit
than ordinary sand. and are the means
of cutting OFT the fine edge of cutting
tools. as saw teeth, planes irons, and
the like.
Two plane irons, made of q fine
quality of steel, as near alike as it was
possible for 3 skilled mechanic to
make them, were each hardened in
then hnely sharpened, SO that the edges
of each presented precisely the same
appearance beneath the magniter.
!, These were each inserted in an ordinary
plane and one placed on the oak. the
other on piece of walnut, both pieces
of wood having been previously
dresser. AZ Gut Idlc VI 1VO pOuuuS
pressure, each iron was crowded ior-
ward four inches. On the oak sti K, the
pressure from the rear Indicated $685.
pounds, while with the walnut the in
dicator showed a pressure of over L.
0oU pounds. The irons were both now
: Withdrawn, and the first placed be-
: meath the microscope; the one used on
. the oak presented y general upset APP
pearance. the edge OF the iron showing
: a slight tendency to turn downward,
. there being sufficient heat gene. ated
Ly the friction to partially draw the
temper along the mi. ute edge, which,
} however. would not extend back suit
) Gent to materially affect the wearing
and cutting properties Of the iron if In
: constant use.
The iron used on the piece of walnut
l showed scratch, notched appearance
, all along the minute edge, and by The
: aid of the most accurate means o
, measurement at hand, these notche1
1 were all OF the same depth. but diner
q ent distances apart, proving conclu
r sively that the particles of grit or crys
/ tails which caused them, by being hard
I er than the best mercury-hardenes
/ steel, were all of the same size. ant
!. evenly Distributed rs far as regard
Q depth of deposit in the grain Of tn
9 wood. The small spaces of the ir0l
: edge between these notches or scratches
9 were found nearly IS the entire edg
$ appeared originally, showing agaiI
: that the cellular tissue OF walnut. out
r side its mineral deposits, was reall,
SO ter than that of oak; hence. were j
8 not for these deposits the timber woul,
8 cut much easier. Of course, if the iroI
: had been drawn back and again shove'
! through, the notches would have bee
more apparent and general. increasin,
, each time, and distance showed unit
. the entire cutting edge had been Of il
: self cut of.
. Consulting the laws governing plan
. or vegetable growth. we are tol tina
| all food before becoming lit for assimil
n alton must be reduced to its gaseOu
3 state. Ii this be so, the questio
!. arises, how, or by what methods Q
It plant-growth and assimilation. is
+ poss. bic for silica to appear in its orig
|, inal crystalline state among the tissue
J, of the growing or mature tree. while
Q is universally known that this variet
o of Wood rows only where this miners
q is abundant in some of its modihe
/ forms. This, however. is not of grea
o interest to manufacturers just how
!. gets there, but thats it present
g shown conclusively.. To gefrid of il
d even were it possible. would destro
: the beauty and general characteristic
d of walnut, and to overcome its actio
. on tools, rapid motion and softer iro
{. is the best, safest and most efticaciou
o method. -Lunber Trade Journal.
70 The seventeen-year-Nld girl VIII
n annually cuts her fathers entire Gro
:. Of wheat and mows ten acres OF gra'
o lives in Union County this year. b
II sides performing these agricultur'
d labors, she has ''set up with stol
y clerk three nights week. read seve
d continued stories in : weekly tamil
d journal. attended four Sunday-scho
~ .>s>~,r~ .of fha dov On kWentv-pig