The quality known as hardness, which some water has, is due to the lime which it has dissolved in making its way through the earth.
Water is said to be temporarily or permanently hard according to the kind of lime it has in solution. Temporarily hard water may be softened by boiling; the lime will be deposited, as may be seen in the "furring" of tea-kettles. Boiling has no effect in softening permanently hard water, so a substance known as an _alkali_ is used for this purpose.
(3) Methods of softening water by alkalies.--For each gallon of water use one of the following: (_a_) One tablespoonful of borax or ammonia dissolved in one cup of water.
(_b_) Two tablespoonfuls of a solution made by dissolving one pound of washing soda in one quart of boiling water.
(_c_) One fourth tablespoonful of lye dissolved in one cup of water.
2. Alkalies (borax, ammonia, washing soda, lye):
(1) Use: (_a_) To soften hard water (_b_) To a.s.sist in dissolving greasy substances.
(2) Kinds: (_a_) _Borax._--This alkali is one of the mildest, and for this reason is less harmful to the clothing. It is useful when an alkali is required to soften water for coloured clothes or woollens. It also has a tendency to keep white clothes a good colour.
(_b_) _Ammonia._--This also is a mild alkali, but is apt to "yellow" white materials. As it is very volatile, it should not be used unless the washing can be done quickly.
(_c_) _Washing soda._--This is a cheap substance and stronger than borax or ammonia.
It should be made into a solution before it is used, for fear of too great strength.
(_d_) _Lye, or caustic soda._--This alkali is very strong and should be employed with great care. It must not be used except in weak solutions, otherwise it would entirely dissolve fabrics. It is not advisable for home laundry work.
3. Soap:
(1) Use.--To act on greasy matter.
Soap-suds penetrate fabrics more completely than water alone, and when the soap comes in contact with fatty material, it _emulsifies_ it, that is, very finely divides it into minute particles, so that it can be easily removed. If a soap is used that contains free alkali, this substance unites with the greasy impurities to form new soap which has cleansing value.
(2) Kinds.--(_a_) Neutral, (_b_) medium, (_c_) strong.
All soap is a compound of an alkali and fat, and according as one or the other of these substances predominates, the kind of soap is determined.
When just enough alkali is used to completely _saponify_ the amount of fat, the product is called a neutral, or mild, soap. When an excess of alkali is present, the soap is termed medium or strong, according to the amount of free alkali it contains.
A mild soap should be used when free alkali would be injurious, as in washing woollens or fabrics that have delicate colours.
4. Soap subst.i.tutes, or adjuncts:
(1) Use.--To act alone or with soap in exerting a solvent action on greasy impurities, so that the cleansing process may be facilitated.
(2) Kinds: (_a_) _Alkalies._--These must be used in excess of the amount needed for softening the water.
(_b_) _Harmless solvents, such as turpentine, paraffin, coal-oil, gasolene._--The clothing must be well rinsed to get rid of any odour.
(_c_) _Washing powders._--These are prepared mixtures of soap and some other solvent of greasy matter.
5. Blueing:
(1) Use.--To make clothes which have a yellow tinge appear whiter in colour.
(2) Kinds.--There are several kinds on the market, but the names of these will be of no value to the cla.s.s.
NOTE.--Sufficient blueing should be used to make the blueing water a pale sky-blue colour when a little of it is lifted in the hand.
6. Starch:
(1) Use: (_a_) To stiffen fabrics and thus improve their appearance.
(_b_) To give fabrics a glazed surface, so that they will shed dust and other impurities.
(2) Kinds.--(_a_) Cold starch, (_b_) boiled starch.
Raw starch does not give as durable a finish as cooked starch, but it does give greater stiffness. A fabric will take up more starch in the raw form, and the heat of the iron cooks the starch, thus producing the stiffness. The "body", or stiffness, produced by cooked starch is usually preferable, though on account of its preparation, it is not so convenient to use.
(3) Recipes for starch-- (_a_) Cold Starch
2 tbsp. laundry starch 1/2 tsp. borax 2 cups cold water.
Dissolve the borax in a little boiling water. Add the cold water gradually to the starch and mix thoroughly. Add the dissolved borax and stir well before using.
(_b_) Boiled Starch
2 tbsp. starch 4 tbsp. cold water 1/2 tsp. lard, b.u.t.ter, or paraffin 1 qt. boiling water.
Mix the starch with the cold water until free from lumps. Add the lard, then gradually stir in the boiling water, and keep stirring until thickened. Cook fifteen minutes and use hot.
NOTE.--Borax in starch gives greater gloss and increases the stiffness. It also gives more lasting stiffness. Lard, b.u.t.ter, or wax is used to give a smoother finish and to prevent the starch from sticking to the iron.
LESSON II
PREPARATION FOR WASHING WHITE LINEN OR COTTON CLOTHES
1. Sort the clothes: (1) Table linen and clean towels (2) Bed and body linen (3) Handkerchiefs (4) Soiled towels and cloths.
2. Mend the clothes.
3. Remove stains.
4. Look after necessary materials.
PROCESS OF WASHING WHITE LINEN OR COTTON CLOTHES
_Steps_ _Method_
1. Soaking:
Wet the clothes; rub the soiled parts with soap and roll each article separately; pack in a tub, placing the clothing most soiled at the bottom; cover with warm soapy water and soak from one hour to over night.
The soaking softens and loosens the fibres of fabrics, so that the foreign matter in them can be more easily separated. It also dissolves the soluble impurities in the fabrics.
2. Rubbing:
Wring the clothes out of the soaking water, and place them in a tub of clean warm water or soap-suds; rub the soiled parts first on one side and then on the other, using the knuckles, a washboard, or a washing-machine. When each piece is clean, wring it tightly.
The rubbing sc.r.a.pes or rubs out the foreign matter which has been loosened by the soaking.
3. Rinsing: