Licence: Public Domain Mark
Credit: Pharmacy. Source: Wellcome Collection.
Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.
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![longing to it are the least constant in their properties, and most subject to decaj’^, it becomes necessary to give a few general rules for their collection and pre- servation. Vegetable matters should be collected in the coun- tries where they are indigenous ; and those which grow wild, in dry soils and high situations, fully ex- posed to the air and sun, are in general to be pre- ferred to those which are cultivated, or which grow in moist, low, shady, or confined places. Roots which are annual should be collected before they shoot out their stalks or flowers; biennial roots in the autumn of the first, or spring of the second year ; perennial roots either in spring before the sap has begun to mount, or in harvest after it has re- turned. Those which are worm-eaten, except some resin- ous roots, or which are decayed, are to be rejected. The others are immediately to be cleaned with a brush and cold water, letting them lie in it as short a time as possible ; and the fibres and little roots, when not essential, are to be cut away. Roots which consist principally of fibres may be immediately dried. If they be juicy, and not aro- matic, this may be done by heat, not exceeding 100<^ of Fahrenheit; but if aromatic, by simply exposing them, and frequently turning them in a current of dry air; if very thick and strong, they are to be split or cut into slices, and strung upon threads; if covered with a tough bark, they may be peeled fresh, and then dried. Farinaceous roots are to be dipt in boil- ing water before they are dried. Such as lose their virtues by drying, or are directed to be preserved in a fresh state, are to kept buried in dry sand. Ginger is usually peeled and preserved in syrup. No very general rule can be given for the collec- tion of herbs and leaves ; some of them acquiring activity from their age; and others, as the mucila- ginous leaves, from the same cause, losing the pro- perty for which they are officinal. Aromatics are to be collected after the flower-buds are formed, an- nuals, not aromatic, when they are about to flower, or when in flower, biennials before they shoot, and perennials before they flower, especially if their fibres become woody. ' They are to be gathered in dry weather, after the dew is off them, or in the evening, before it falls, and are to be freed from decayed or foreign leaves. They are usually tied in bundles, and hung up in a shady, warm, and airy place ; or spread upon the floor, and frequently turned. If very juicy, they are laid upon a sieve, and dried by’^ a gentle degree of artificial warmth. Sprouts are collected before the buds open ; and stalks are gathered in autumn. Barks and woods are collected in spring or in autumn, when the most active parts of the vegetable are concentrated in them. Spring is preferred for resinous barks, and autumn for the others which are not resinous, but rather gummy. Barks should be taken from young trees, and freed from decayed parts, and all impurities. The same rules are to be followed in collecting woods, which, however, must not be taken from very young trees. Among the re- sinous woods, the heaviest, which sink in water, are selected. The alburnum is to be rejected. Flowers are to be collected in clear dry weather, before noon, but after the dew is off', either when they are just about to open or immediately after they have opened. Of some the petals only are preserved, and the colourless portions are even cut away ; of others, whose calyx is odorous, the whole flower is kept. Flowers which are too small to be pulled singly are dried with part of the stalk; these are called heads or tops. Flowers are to be dried nearly in the same maimer as leaves, but more quickly, and with more attention. As they must not be exposed to the sun, it is best done by a slight de- gree of artificial warmth ; and in some cases they should be put up in paper bags. When they lose their colour and smell they are unfit for use. Seeds and fruits, unless when otherwise directed, iU'e to be gathered when ripe, but before they fall spontaneously. The emulsive and farinaceous seeds are to be dried in an airy, cool place ; the mucilagin- ous seeds by the heat of a stove. Some pulpy fruits are freed from their core and seeds, strung upon thread, and dried artificially, by exposing them re- peatedly to the heat of a stove. They are in general best preserved in their natural coverings, although some, as the colocynth, are peeled, and others, as the tamarind, immersed in syrup. Many seeds and fruits are apt to spoil, or become rancid; and, as they are then no longer fit for medical use, no very large quantity of them should be collected at a time. The proper drying of vegetable substances is of the greatest importance. It is often directed to be done in the shade, and slowly, that the volatile and active particles may not be dissipated by too great heat: but this is an error; for they always lose infinitely more by slow' than by quick drying. When, on ac- count of the colour, they cannot be exposed to the sun, and the warmth of the atmosphere is insufficient, they should be dried by an artificial warmth, less than 100° Fahrenheit, and exposed to a free current of air. When perfectly dry and friable, they have little smell; but, after being kept some time, they attract moisture from the air, and regain their proper odour. The boxes and drawers in which vegetable substances are kept should not impart to them any smell or taste ; and, more certainly to avoid this, they should be lined with paper. Such as are volatile, of a delicate texture, or subject to suffer from insects, must be kept in well-covered glasses. Fruits and ^oily seeds, which are apt to become rancid, must be kept in a cool and dry, but by no means in a warm or moist place. Oily seeds, odorous plants, and those containing volatile principles, should be collected fresh every year ; others, whose properties are more permanent, and not subject to decay, will keep for several years. Vegetables collected in a moist and rainy season, are in general watery, and apt to spoil. In a dry season, on the contrarjq they contain more oily and resinous particles, are more active, and keep much better. We may now proceed to examine the mechanical I operations of pharmacy, commencing with the best ■ mode of determining the weight and bulk of those ■ bodies employed by the pharmaceutical chemist. For I this purpose there should be sets of beams and H scales of different sizes ; and it w'ould be advisable to H have a double set, one for ordinary use, and another ■] for occasions when greater accuracy is necessary. A A good beam should remain in equilibrium both by W itself and when the scales are suspended, one toW either end indifferently; and it should turn sensibly ■! with a very small proportion of the weight with* which it is loaded. Balances should be defended as li](https://iiif.wellcomecollection.org/image/b22466381_0004.jp2/full/800%2C/0/default.jpg)
