Omaha daily bee., 1899-07-02

precautions to see that she gets what she
pays for. The means necessary to assure fair
play are too simple not to be universally put
in operation. All she need do Is procure a
sample of such goods as she proposes buy
ing, submit 1t to the proper tests, and proof
positive Of the component parts Of the ma
terial will be at once forthcoming.
To understand the application OF these
tests it must be remembered that all tex
tiles are made Of twisted yarns. the threads
running lengthwise called the warp and
those extending from sevage to selvage
called the woof or weft. Two-ply yarns are
formed by twisting two single yarns to-
gether before the fabric is woven, and a
common method Of adulteration is in twist
ing a wool and cotton, or a silk and cotton
yarn together. Such yarns are seldom used
in the weft, SO it will only be necessary to
examine a warp yarn. Untwist the yarn,
and If double two distinct threads will ap-
pear; II single, all the twist will be re-
moved and 1t can be easily separated.
Tests for Shorts and Shoddy.
Worsted, mohair, alpaca and shoddy are
subject to the same tests as wool. The high
priced fabrics-silk wool and linen are
adulterated with cotton most commonly.
Untwist single yarn and examine the aver
age length of the fbers under a strong
| reading glass or microscope. II the silk and
linen fbers average less than one and n
half inches in length, the wool fibers less
than one inch, and the cotton less than
three-quarters Of an inch you may feel sat-
! isfied that the fabric will not wear we'll
The simplest manner of testing wool or
part wool fabric for the presence OF cotton
is by fire. Remove two or three warp yarns,
and, after determining whether they are
single or ply yarns, take one and light an
end. If 1t burns slowly, emitting the pun
gent odor characteristic OF burnt hair Il "
all wool, II 1t flashes up and burns rapidly
without odor II is cotton.
Analytical chemists and expert buyers use
acids to determine the presence and amount
OF cotton in a so-called wool fabric. II the
instructions here given are followed closely
| anyone can make the test satisfactorily,
1t is necessary to use sulphuric acid, and
this is extremely dangerous to handle In
It's pure state. Even In the dilute form
great care must be taken not TO allow drop
OF 1t to touch anything but the fabric 10 be
tested, as It viii burn and discolor,
To avoid trouble, lot the chemist make n
so per cent solution; 10 cents worth Is
enough for several tests 4 sample one or
two inches square is sufficient for expert
mont; place this In glazed oarthcnware
or porcelain lined dish, Put In enough OF
the solution TO cover the cloth we'll, then
over slow hrc steep until change is
noted In tho sample; afterward allow tho
solution to cool before removing tho bit OF
goods. Compare the sample tested with the
original cloth. II the former looks like n
sieve 1t indicates that part OF the warp
yarns are cotton II tho fabric has fallen
apart they are all cotton; while II only n
little sediment remains the fabric is prac-
ticafy pure cotton. II unchanged after dry
ing in dark. cool place the stun is all
wool. The acid solution dissolves the cot
ton in the fabric and It's only action on wool
is to turn II a dirty red color.
To Test SILK.
The quality OF silk fabrics is tested In
similar manner. but a different acid is
used and 1t is not necessary to boil It. OBJ
tain 8 per cent solution OF nitric acid;
cents worth will be enough for many
tests. Remove a few OF the warp yarns
from the sample and dip them in the So
luton one at time. II they are silk they
will turn yellow II of cotton or other yege-
table ibers they will suffer no change. Re
peat the process with the weft yarns. It
simplihes matters to know that when cot
ton is used to adulterate silk fabrics II Is
always found In the warp, Cheap satins
and some other heavy silks are so woven
as to show pure silk face, or right side"
while the back is all cotton These may
be roughly tested by letting fall a single
drop OF the solution upon the back and then
another upon the face, at the same time
looking for the dscoloration noted
process has recently been nerfected by