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A HYACINTH GLASS STAND.-CHRYSANTHEMUM PATTERN.

centre on to a string, net two rows all round, netting at the corners four stitches into one loop. There should be twenty-five loops at each end, and sixty-four down each side. Count the number of stitches, and mark with coloured cotton each corner. With wide mesh net ten loops into the stitch next the coloured mark at the end, but not at the side, miss seven loops, net ten into the eighth

BY MRS. WARREN.

loop, *; then miss three loops; net ten into the fourth, repeat from * again, then miss seven loops; net ten into the eighth; (this will be the loop immediately before the coloured mark); net ten into next loop, which will be immediately after the coloured mark; miss seven loops, net ten into the eighth, t miss three loops, net ten into the fourth, repeat from † three times more, then miss

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NETTED D'OYLEY FOR TARTLET. BY MRS. WARREN,

four loops, net ten into the fifth, repeat from | ton, tie it into the loop directly over the twice more miss three loops, net ten into the fourth, continue to repeat from § till the corner, where net as at the other corner; then continue along the end and side the same as the one just netted. With narrow mesh net four rows all round. This will make two diamonds. Cut off the cot

coloured mark, net nine stitches, T (or turn on reverse side), net eight stitches, thus missing one, and continue turning and decreasing a stitch at the end of every row till the netting is reduced to a point. Continue this all round. Darn as in engraving with the Trafalgar cotton and long needle.

THE PHYSIOLOGY OF HEALTH AND DISEASE.

CHAPTER THE EIGHTH.

ON WATER, AND AMYLACEOUS ARTICLES OF DIET.

FROM what has been said in the previous chapters on the structure of the body, it will be seen that water forms an important part in its functions. In the very earliest conditions of the existence of or ganic being, we find water necessary. The cells of the various cellular algæ, as those of the red snow-plant, the cells of minute fungi, and the germinating tissues of the embryo of every seed, must have water supplied before they will begin to grow. During the progress of the growth of every plant, water must be supplied, either in a liquid or a gaseous form, or they would cease to live. It is the same with the animal world. No ovum will develop the embryo creature it contains, and no animal, however small, will live, unless it is supplied with water. It is true, that the power of growth is often retained for marvellously long periods of time in the seeds of plants and the ova of animals; but in all cases where the functions of life are exhibited, there must water be present. An examination of the composition of the human body will at once show that it is no exception to this law of animal life. The blood which circulates through our body contains, in every 1,000 parts, 790 parts of water; whilst the muscular substance--the flesh itselfcontains, in every 1,000 parts, 770 parts of water. Now it is very clear, that this fluid must be supplied to the body from without; and it is taken in in no other way than by the mouth, with the food. But not only is water necessary for the supply of this material in the body, but also to supply the waste which it sustains. The water from the body is constantly passing away in the secretions; but more especially in the perspiration from the skin. It is by means of the water which passes off from the skin that the heat of the body is regulated; and just as the heat which enters a tea-kettle of boiling water is got rid of by the steam, so the heat that is generated in the human body is got rid of by means of the perspiration which is constantly passing from the skin. To maintain the due fluidity of the body, and to regulate the heat of the body, are the two offices of water in the human

system. Hence we find it supplied in all our food; and when it is not in sufficient quantity, we make up for it by supplying it in the solid food in the form either of water itself, or in infusions-as tea, coffee, and chocolate, or in wines and beers.

We shall not enter into any details here on the action of water on the system, but content ourselves with making three observations on the use of water as an article of diet.

First, It may be taken in too large quantities to be carried off by the skin and other emunctories, and then it remains in the system to impoverish the blood, and to reduce the amount of solid matter that is necessary for the performance of the functions of the tissues of the body. This is one of the results that take place from what is called the water cure. Unless persons have sufficient vigour to take the exercise necessary to throw off by the skin the water that is taken into the stomach, serious ill effects must necessarily arise. The good that is effected by this system of the treatment of disease must be attributed more to the exercise that it renders necessary than to the unnatural quantities of water that are taken into the system.

Secondly, Water may not be taken in sufficient quantities to carry on the healthy functions of the system. If the food is taken too dry, it is only imperfectly digested, and many important constituents, such as the salts, are not taken into the body in sufficient quantity. A deficient quantity of water in the blood will also prevent the healthy process of nutrition, and wasting and degeneration of the solid parts of the body will occur. It would be difficult, perhaps, to lay down any law with regard to the quantity of water individuals should take, and perhaps it is safer to rely on the instincts of the body, which seem to point out how much we ought to take by the feeling of satiety that comes on after enough has been taken. We may, however, get at something like an approximation of the proportion of solids and fluids required by the system in food by examining the composition of milk, in which we find the proportion of water to solid parts is as 870 to 130 in 1,000 parts, or about as seven to one.

Thirdly, The good effects of water may be destroyed by the substances with which it is taken. Although the stomach has the power of separating water from the food in which it exists, it yet often happens that the fluid articles of diet are injurious. Water itself may contain so large a quantity of saline matters, or of organic matters in

state of decomposition, as to cause serious disease. The taking habitually water in the form of fermented liquors, as beer and wine, as also the admixture of distilled spirits, may cause irritation and congestion of the mucous membranes, and derangement of the nervous system.

With these general remarks, we must dismiss the group of aqueous substances used as food, and proceed to speak of the carbonaceous group. This class of substances is sometimes called respiratory, and combustible. They are called respiratory, because it is through the function of respiration that they become useful in the system. They are called combustible, because it is through the process of combustion that their effects upon the system are developed. This class of foods does not, in fact, contribute directly to the nutrition of the body, but they are consumed in maintaining the animal heat. The temperature of the human body is always a fixed one; and if we place a thermometer upon the tongue, or, under the arm, or in any other unexposed part of the body, we shall find that it stands at the point in the index of Fahrenheit's thermometer marked 98°. This heat the human body maintains equally at the poles and under the tropics. No external temperature alters it, and we have thus conclusive evidence that it is produced from within. The cause of this heat is the combustion of the carbon and hydrogen contained in the carbonaceous group of foods. Starch, sugar, and oil, are conveyed from the stomach into the blood, and whilst in the blood they are brought in contact with oxygen gas, which is taken in during respiration, and the consequence of this contact is the union of the carbon and the hydrogen with the oxygen, the formation of carbonic acid gas and water, and the giving out of heat. This process in the blood is of exactly the same nature as that which occurs during the burning of a fire or candle in the open air. The carbon and hydrogen of the coal and the tallow combine with the oxygen of the atmosphere, carbonic acid gas and water are formed, and heat and light given out. The only difference between the two processes is, that during the production of the animal heat no light is given out; but this is accounted for by the low temperature at which the combustion takes place.

The human body is preserved at the same temperature by the regulating action of the skin. When large quantities of heat are generated in the body, by exercise or other causes, then the extra heat is carried off by the perspiration from the skin; but when

the body is exposed to a low temperature, and its heat is rapidly conducted away by surrounding cold, the heat is maintained by increased supplies of food belonging to the carbonaceous group. The animal heat of the lower animals varies according to the circumstances of the creature. Those performing great muscular exertions, and living in cold climates, have a higher temperature than man; whilst those which are not active in their habits, and live in hot climates, have a temperature lower than that of man.

These remarks will serve to indicate the nature of the influence the substances found in this group exert as food. Although the plants from which they are derived are very various, yet the substances themselves are very few, and are principally starch, sugar, and oil. We shall first speak of starch, or amylum, as it is often called. Starch, when separated from the flour of wheat, is well known on account of its domestic uses; but starch is the same compound chemically, from whatever plants it is procured. Starch is extensively employed in our textile manufactures, to give firmness to linen and cotton fabrics; hence it is prepared in large quantities for manufacturing purposes. Beautiful specimens of this substance were to be seen in the Great Exhibition, in the Classes III. and IV., where it was exhibited both as an article of food, and a raw vegetable product. In the vegetable kingdom starch is a very widely diffused body. In almost every growing cell granules of starch may be distinguished by means of the microscope. These granules are of various sizes, and assume a great variety of forms; some are round, others are flat, whilst others are even stellate. These granules are always found mixed with other substances, but they are easily made distinguishable by the application of a little iodine, which is one of the best tests for starch, and which, coming in contact with it, produces a beautiful blue colour.

Starch is found in some plants in greater quantities than in others; it is, however, very generally found in perennial roots and rootstocks, in the stems and in the seeds of plants. It seems stored up in these parts for the future growth of the developing organs of the plant. There are few or no vegetables or parts of plants that are eaten, that do not contain starch. We find it in turnips, carrots, potatoes, cabbages, parsnips, beans, peas, wheat, barley, oats, and the rest of the Cerealia; in chesnuts, walnuts, hazelnuts, and all other seeds; in the apple, the pear, the plum, the cherry, and all other fruits. In many of these things, however,

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Fig. 19. The East Indian is produced by another species, the M. Indica, (Fig. 18, B.) What is called Tous les Mois is obtained from another genus of marantaceous plants, and is called Canna Edulis. The part of the plant from which the starch is obtained is the same in all these cases, and the mode of preparation the same. Plants belonging to this family have what is called, botanically, a rhizoma, or rootstock (Fig. 19, a) an organ standing between the root and the stem. In this rootstock the starch is deposited, and it is separated in the following manner :-The rootstock is dug up, and then bruised and placed in water. The heavier parts, con

a

(C)

Fig 19.-Maranta arundinacea - ARROWROOT. sisting of woody tissue and other matters, fall to the bottom of the water, but the starch is diffused through the water. The water, with the starch, is then separated, and allowed to stand, when, at the end of some hours, the starch falls to the bottom of the water; it is then collected and dried. This is the principle on which all starch is separated from the tissues in which it is developed. By the same process starch may be procured from potatoes, carrots, turnips, and the stems, leaves, and seeds of plants. Although there is much difference in the What is sold under the name of arrow-price of arrowroot, its composition is always root in the shops, is a form of starch procured from the rootstocks of various species of plants belonging to the family Marantacea. There are three kinds of arrowroot known in the shops,-the West Indian and East Indian arrowroots, and the Tous les Mois. The West Indian is the produce of a species of Maranta, called M. arundinacea,

Fig. 18.-Granules of Starch.-(A) From wheat and barley. (B) From arrowroot. (C) From Portland sago.

the same. Even the substances used to adulterate arrowroot, as potato and sago starch, are of the same composition, and, although the appearance and flavour of the arrowroot may be impaired, its ultimate dietetical action is the same.

Although arrowroot, sago, tapioca, and potatoe starch are all composed of the same

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