658. Flour of Brimstone

is a mild aperient in doses of about a quarter of an ounce; it is best taken in milk. Flour of brimstone, which is also called sublimed sulphur, is generally put up in ounce packets at 7d.; its wholesale price is 4d. per pound.

[A SPARK MAY RAISE AN AWFUL BLAZE.]

659. Medicines.

Preparations of them.--The following directions are of the utmost value in connection with the DOMESTIC PHARMACOPOEIA, DISEASES, PRESCRIPTIONS, and POISONS.

_They will be found most important to emigrants, attendants upon the sick, and persons who reside out of the reach of medical aid, sailors, &c., &c. They contain instructions not only for the compounding of medicines, but most useful hints and cautions upon the application of leeches, blisters, poultices, &c._

660. Articles Required for Mixing Medicines.

_Three gla.s.s measures_, one to measure ounces, another to measure drachms, and a measure for minims, drops, or small doses.

A _pestle and mortar_, both of gla.s.s and Wedgwood-ware.

A gla.s.s funnel.

Gla.s.s stirring rods.

A _spatula_, or flexible knife, for spreading ointments, making pills, &c.

_A set of scales and weights_.

_A small slab of marble_, or porcelain, for making pills upon, mixing ointments, &c.

661. Medicine Weights and Measures.--_Weights_.

When you open your box containing the scales and weights, you will observe that there are several square pieces of bra.s.s, of different sizes and thicknesses, and stamped with a variety of characters. These are the weights, which may now be explained.

662. Troy Weight.

Medicines are made up by troy weight, although drugs are bought by avoirdupois weight. There are twelve ounces to the pound troy, which is marked lb.; the ounce, which contains eight drachms, is marked [*ounce]i. [looks like a z on top of a 3]; the drachm, containing three scruples, is marked [*drachm]i. [looks like a 3]; and the scruple of twenty grains is marked [*scruple]i. [looks like a backwards C with a horizontal cross-bar]. The grain weights are marked by little circles, thus:

-------

o o

Five

o

Grains

o o

-------

Each of the grain weights, in addition to the circles denoting their several weights, bears also the stamp of a crown. Care must be taken not to mistake this for one of the numerals. Besides these weights there are others marked [*scruple]ss, which means half a scruple; [*drachm]ss, meaning half a drachm; and [*ounce]ss, meaning half an ounce. When there are ounces, drachms, or scruples, the number of them is shown by Roman figures, thus:--i. ii. iii. iv. v., &c., and prescriptions are written in this style.

663. Measures.--Liquid

Liquid medicines are always measured by the following table:

60 minims......... / 1 fluid drachm.

8 fluid drachms

are

1 fluid ounce.

20 fluid ounces...

contained

1 pint.

8 pints.......... / in 1 gallon.

And the signs which distinguish each are as follows:--c. means a gallon; o a pint; _fl_ [*ounce], a fluid ounce; _fl_ [*drachm], a fluid drachm; and m, a minim, or drop. Formerly drops used to be ordered, but as the size of a drop must necessarily vary, minims are always directed to be employed now for any particular medicine, although for such medicines as oil of cloves, essence of ginger, &c., drops are frequently ordered.

664. Specific Measuring Vessels.

In order that Medicines may be measured Accurately, there are graduated gla.s.s vessels for measuring ounces, drachms, and minims.

665. Approximate Measures.

When proper measures are not at hand, it is necessary to adopt some other method of determining the quant.i.ties required, and therefore the following table has been drawn up for that purpose:

A tumbler ....... / 10 ounces.

A teacup ........

6 "

A winegla.s.s ....

usually

2 "

A tablespoon.....

- contains -

4 drachms.

A dessertspoon...

about

2 "

A teaspoon....... / 1 "

These quant.i.ties refer to ordinary sized spoons and vessels. Some cups hold half as much more, and some tablespoons contain six drachms. A medicine gla.s.s, which is graduated so as to show the number of spoonfuls it contains, should be kept in every family.

[TO-DAY, MAN LIVES IN PLEASURE, WEALTH AND PRIDE.]

666. Process of Making Medicines.

To Powder Substances.--Place the substance in the mortar, and strike it _gently_ with direct perpendicular blows of the pestle, until it separates into several pieces, then remove all but a small portion, which bruise gently at first, and rub the pestle round and round the mortar, observing that the circles described by the pestle should gradually decrease in diameter, and then increase again, because by this means every part of the powder is subjected to the process of pulverization. In powdering substances, making emulsions, and whenever using a mortar, the pestle should always travel _from the right to the left_.

667. Preparation and a.s.sistance.

Some substances require to be prepared in a particular manner before they can be powdered, or to be a.s.sisted by adding some other body. For example, camphor powders more easily when a few drops of spirits of wine are added to it; mace, nutmegs, and such oily aromatic substances are better for the addition of a little white sugar; resins and gum-resins should be powdered in a cold place, and if they are intended to be dissolved, a little fine well-washed white sand mixed with them a.s.sists the process of powdering. Tough roots, like gentian and calumba, should be cut into thin slices; and fibrous roots, like ginger, cut slanting, otherwise the powder will be full of small fibres. Vegetable matter, such as peppermint, loosestrife, senna, &c., requires to be dried before it is powdered.

668. Care of the Mortar.