The Greenville times. [volume] (Greenville, Miss.) 1868-1917, 1885-06-20
THE PATIENCE OF METALS.

We take the following paragraph
from DR.. Perey's address delivered
before the Iron and Steel Institute
May 9th: We hear in these days
of the fatigue REFRESHMENTS
aud patience of metals, terms
which, when applied to inanimate
objects, may bewilder the uninitia.
ted, and at first perhaps the initia-
ted. When metal is subjected
to mechanical treatment which
produces what is called stress or
strain,its component PARTICLES may
become so distributed and disar-
within the limits of elastic.
ity be it understood, that, after its
withdrawal from such treatment,
and left at rest, some time, and in
certain cases considerable time,
must elapse before the particles
will have spontaneously readjust.
ed themselves as they originally
were. The word fatigue, | appre-
bend, is meant to indicate such
disturbance; the word refresh.
ment, restoration of the metal to
its original state; and the word
patience, the time required for that
restoration. So lately as February
last a paper was read to the Amer
lean Institute of Mining Engineers
by Mr.. Henry NJ. Howe, Boston,
on the patience of copper and sill
yer as affected by annealing on
which he had experimental. His
results possess considerable inter.
est. He refers to the experiments
of Prof r. II. Thurston on the re.
sistance of iron to prolonged
stress, which show that as uuan.
nealed iron greatly exceeds in
tensile strength the same iron
when annealed, a fact long previ.
ously known, so it likewise greatly
exceeds the latter in patience. |
must refer you to original papers
for information as to the numeri.
cal and other details, because
time forbids that ! should do more
than notice the subject on the
present occasion. The power, Mr..
Howe remarks, of resisting pro.
longed stress bears no fixed rela.
tion to what is commonly called
tensile strength or the power of
resisting tensile stress for very
short time. He suggests that the
word endurance might be more ap.
propriate than patience for ex'
pressing the former kind ofpower
A paper on the influence of stress
and strain on the physical proper.
ties of matter has recently Decem
Der, 1884 been communicated to
the Royal Society by Mr.. Herbert
Tomlinson, in which is contained
matter of interest and of practica
Importance in reference to the ap
plication of iron wire. He fluids
the loss of energy of a torsionall,
vibrating iron wire to be perma
nently diminished to q very larg,
extent by repeated heating to 1O'
degrees c., and cooling combine,
with long rest, and to be consider
ably diminished temporarily by ris'
of temperature. There is wide
spread impression, not to say be
lief that razor when left at res
for some time after use become
sharper spontaneously. The mum
ber of persons having the oppoI
tunity of personally experimenting
on this important question ha
greatly decreased in recent years
yet some remain who still practic
the tonsorial art and it must b
left to them to determine whethe
that impression be erroneous o
not. Seould it prove to be col
rect, then the razor might proba
bly, be adduced as affording an il
lustrstion of fatigue, refreshment
and patience. Is it not strang
that on such simple practica
question as this opinion should stiI
be divided