The times dispatch. [volume] (Richmond, Va.) 1903-1914, 1913-02-02

times and nearly three-quarters of
/ century.
But. coming near home. rle old
Richmond Theatre on Broad Street was
/ severed when built. more than sixty
/ years ago. with the Buckingham blue
/ black slate. The old theatre was
pulled down some years ago, and the
contractor finding the roof IN perfect
( condition saved the slate and used II
/ in roofing two smaller houses in the
! northern part of the city, and 1t Is
/ doing service thereon TO this day, ana
unless broken up by fire and fremen
or destroyed in some way by the manu-
. of man. Will keep on doing service 10
the end Of time.
Little No Lime.
do not mean to make light OF Pro-
fessor Dale's technical description OF
buckingham slate, for there may De
those among my readers who can un-
derstand it. For their benefit ! VIII
give the analysis of this slate, which
is as follows:
"The sample dried at PIP de
rrees Fahrenheit contains: silica
so e5 per cent alumina 1854
per cent: ferri-oXid 3.iS per
cent: magnesia. trace; lime (Ca o..
19f per cent: magnesia tMz o. z-@'
per cent: carbon dioxide. trace; SUI
nhur. SO per cent: potash. $50 per
cent: soda. 21S per cent; water ana
organic matter, 3.65 per cent
IL will be observed that the ohly
constituent found in the above that
can possibly be subject to discolor-
inc and consequent dsinteeration is
lime and the percentage of that is so
small that il could not have any APP
preciable effect l am told that IN
tho clay states the percentage OF lime
is from FIVE 10 fifteen times as great
To those who understand an analysis
when they read II the above SHOWS
conclusively the tensile strength OF
this famous blue-biack of Bucking-
ham.
There is a way. however, that one
who does not understand the technlcal
terms can tell what is superior ana
what is inferior in slate. That which
will not lose its color will not dis
integrate and that which will not
discolor contains metallic constituents
which give it a ringing sound when
struck with an implement or with
the hand The clay states that Will
discolor and then disintegrate Will
not ring. Every piece that is taken
from this Buckingham deposit. when
dressed and made into the shinGie
shape. will ring almost like bell
when held up and struck with the
hand or with any kind of implement
The experts tell me that when a piece
Of slate stands this test il may be
sure that it is indestructible.
Uses of Good Slate.
As already stated these buckingham
slate ouarries have been worked for
more than half century. but there
seems to be as much slate here now as
ever. There are yet many acres, even
miles of the lands loaded with slate
that can he developers to add TO the
wealth Of Old virginia. More slate
is being taken out now than ever
before, and there can be no doubt that
the amount of the output Will from
now on grow rapidly. for economic
uses to which slate can he put are
RAPIDLY Increasing. being proportion
ate to the commercial strides in every
direction. The increasing familiarity
with the blue-black slate, and its
superiority over products sinrlarly
used. because of its nonporous char
acter. its durability and its electrical
on-conductivity. is rapidly being re-
c0gnized In short there is no sub
stance equaling high grade mica
in any capacity where it is used. for
no other material. used for the same
purposes as blue-black slate. has any
thing like the latter's efficiency.
The three purposes for which slate
is chiefly used are for roofing. cleo
trical and structural work. Slate roof
ing purposes has been in use to a
greater or less extent for centuries.
hut its advantages for this purpose
on account Of It's durability. its non
iurammabiiity. resistance TO FIRE and
lighting. are being increasingly rccog-
nized In short. the demand 20 rslate
has. probably. increased chiefly as the
result ~ some Of the same Industrial
agencies that have caused the great
phenomenal growth Of the Portland
cement industry. with. however. this
. difference that the material suitable
for the manufacture OF cement j.
mach more widely distributed. while
slate deposits q economical import
ance are relatively 9csrce.
superior HoofinE Material
The initial cost 81 slate roofing Is
really but little higher than the best
Grade of wood shingles. and but
slightly more than tiu. Moreover. the
wood shingles VIII decay. and the tin
ras 90 b. painted every two or three
Years. and at that 10 viii rust and re-
quire replacing iu a few years. while
% superior slate like the BuckinRham
blue black will iass-wcli no man
lives Ions enough t. SAY just how
icug-but 10 ls practically indestruc-
tibie
Again. there is az erroneous idea
that iu order O. carry n slate roof
house must he constructed more
strongly than for shingles. whereas.
as q matter 20 fact. any Substantially
built house can carry slate without
ans strain whatever. Then also the
difference in weight is compensated
Tor BY reason ~ tEe fact that IN vim
ter. snow. with its added eeight ciings
t. shingles bui soon slides OF the
slate.
Fire ordinances are being passed IN
all progressive cities and villages. pro
hibitiuG the use 81 any infammabic
material for roofing purposes because
% the fact that fires spread from roof
IL -------- IL L. nd Sill