something which will hold the coloring
matter. Other mordants are oxides, hydroxides, and basic salts of
aluminum, iron, tin, and chromium.

[26] Place a piece of sulphur on a deflagrating spoon and light it by
placing it in the flame and allow it to burn. Cover the bottle by
means of a glass plate.

[27] Bleaching powder is prepared by passing chlorine gas over layers
of slaked lime (lime to which a slight amount of water has been
added). Bleaching powder bleaches by having its hypochlorous acid set
free, which in turn gives up oxygen, being converted into hydrochloric
acid. The French use solutions containing chloride and hypochlorite of
soda. They are called Labarraque's disinfecting fluid. A similar
solution of a mixture of chloride and hypochlorite is called Eau de
Javelle.

[28] A description of shoe and hand clothing may be obtained from
_Shoemaking_, published by Little, Brown & Co., Boston.

[29] In Ireland the cost of producing a pound of bleached linen cloth
4 sq. yd. is 16_d._ or 32 cts.; cost of hackling a pound of flax is
1/2_d._ or 1 ct. per lb.; cost of preparing and spinning a pound of
flax is 6_d._ or 12 cts. per lb.; cost of winding and weaving a pound
of flax is 2-1/2_d._ or 5 cts. per lb.; cost of bleaching and
finishing a pound of flax is 7_d._ or 14 cts. per lb.; $75 is spent in
turning $100 worth of flax into yarn; $75 is spent in turning $100
worth of yarn into brown linen; $50 is spent in turning $100 worth of
brown linen into linen for market.

[30] A linen fabric can be best told from cotton by holding it up to
the light and examining the evenness of the threads. Cotton can be
more easily spun level than flax, therefore threads that present
considerable irregularities may be taken to be flax. In a union fabric
the nap is usually cotton and the threads more regular than the
filling (flax). The best linen is made from fine and fairly regular
threads; common linen from coarse and irregular tow yarns. Linen is no
more subject to weak places in weaving than cotton, although it is
harder to bleach and may be weakened in this process. If each
operation is not perfect the linen will become yellow in storage.

SOURCES OF SUPPLY

The author has found that very nearly all manufacturers are willing to
supply schools with samples of their products. But the demand for
samples has been so great that it is necessary in most cases to pay a
small sum to cover the cost.

The following promine