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Another instance affording a safeguard of human life, and a remedy for a more serious evil : “In needle manufactories, the workmen who point needles are constantly exposed to excessively minute particles of steel which fly from the grindstones, as the finest dust in the air, and are inhaled with their breath; this in time produced a constitutional irritation dependent on the tonic properties of the steel, which was sure to end in pulmonary consumption : insomuch, that persons employed in t'ais kind of work, used scarcely ever to attain the age of forty years. In vain was it attempted to purify the air, before its entry into the lungs, by gauzes or linen guards: the dust was too fine and penetrating to be obstructed by such coarse expedients, until some ingenious person bethought himself of the motions and arrangements of a few steel filings on a sheet of paper held over a magnet. Masks of magnetized steel are now constructed, and adapted to the faces of the workmen. By these the air is not merely strained, but searched in its passage through them, and each obnoxious atom arrested in its progress."

Also Davy's safety-lamp, lightning conductors, etc., are all instances of the application of science to the most valuable purposes of social life.

So indifferent, from habit, do the miners become, in the midst of danger, that to those unaccustomed to this class of life, their conduct appears almost unaccountable. The following was told me, by a scientific friend, as having occurred when visiting a mine of a very dangerous character:

- The workman carrying the light, when he came to a particular part of the mine, stopped, and coolly said, “Now, Sir, if I were to elevate the light a few inches higher, we should be blown to atoms.'” Meaning the light would then come in contact with the carburetted hydrogen which, from its comparative lightness, was floating in the upper part of the diggings.

This dangerous gas, issuing from fissures in small quantities, and sometimes from beds below those the men are working, by means of boring is employed as a gas-jet to light the veins above. Sometimes it is carried to the

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surface of the ground, and a continual fire kept up by it at the surface.

Of the great usefulness of being acquainted, through experiment, with facts in science which are of a practical kind, a knowledge of which, from experience, I am convinced is attainable in our best elementary schools, the following is a striking instance. The philosophy of it is very interesting, and from its being an important practical lesson, I give it here : it shows also, that the very means we take to protect both life and property may, through ignorance, increase the danger we wish to avoid ; and is an instance, where a knowledge of science prevented what might otherwise have been attended with most se. rious results. Being in London, I went with a friend to the Royal Institution, to hear a lecture which had been announced on the manufacture of glass, and on the appli. cation of various metallic substances in colouring it, etc.; on arriving there, we found there was no lecture, some danger of fire having arisen from the furnaces erected for the occasion. On the subsequent Friday, Professor Faraday gave a very interesting account of this accident. The heat of the furnaces and fire resting on the bricks of the fire-place in the lecture-room, had so heated the bricks, as to char the ends of some joists on which the floor rested, and the ends of which ran up nearly to the fireplace, and were in contact with the bricks; this caused a smell of fire, water was thrown on the fire in the fire-place to extinguish it, and while this was being done, a workman went into the room below, and broke the ceiling at a distance from the fire place, and spying every now and then a flame issuing out, thought nothing could stop it. This being pointed out to Professor Faraday, he immediately saw the water thrown for the purpose of putting out the fire, falling on the heated bricks, was decomposed, and the hydrogen, by the pressure of the steam above, was forced downwards, and coming in contact with the charred beams, took fire, the beam ends being sufficiently hot to ignite it, so that the very means taken to extinguish it were adding to the danger. He then directed the water to be thrown on the heated substances near the fire, and these being cooled

down below the point which would cause the gas to ignite, there was of course no further danger in throwing water on the fire.

The facts of a scientific kind connected with this are by no means difficult to understand, and are such as an experi. enced workman, who had seen experiments on the composition and decomposition of water-- how the compound substance could be separated into two others, by coming in contact with a heated surface, like the bricks, and that one of them, hydrogen, was very inflammable, and would ignite at a low temperature--that the oxygen would assist the combustion — would easily understand : the lesson taught him would be, that, in a case of this kind, instead of continuing to throw water on the fire and on the bricks, he would immediately direct it to be poured on the heated materials around, and then pour water again on the fire ; when, even if gas were evolved, there would be nothing near it of a sufficiently high temperature to ignite it.

Facts in science such as these have a direct practical bearing; and when it is seen how much of property in towns, nay, of life itself, may depend upon a knowledge of them among what are called our more experienced workmen, their importance will be understood.

A knowledge of elementary chemistry, and of what has been termed the philosophy of common things, is becoming every day more and more necessary in the schoolmaster, and greater facilities for acquiring it are placed within his reach.

The Training Colleges make it a part of their course of instruction. The managers of schools are now seeing its importance; and influential individuals who take an interest in promoting a good practical education for the industrial classses, are proposing to institute prizes in their own counties and districts for those schoolmasters who shew the greatest knowledge of such subjects, and its application to the comforts of life — with regard to food and its cookery - ventilation of cottages, and sanitary condition of them -a knowledge of mechanics and labourer's work, etc., : such prizes to be adjudged after examination in writing,

and viva voce, by competent persons in the required subjects: and, I would add, as shewn in their application of it, in the state of their schools.

The Committee of Council on Education will aid in providing the necessary apparatus for instruction in elementary physicsl science, in schools where the teachers are competent to use it; and the Board of Trade* Department for the encouragement of Practical Science and Art, at which Dr. Lyon Playfair is secretary for the former, is instituted for the purpose of promoting it, both in schools and other local institutions.

The demand for apparatus connected with this department of teaching is likely to be very great compared with what it has been ; and those employed in its production are turning their attention to simplify and cheapen it. I am told if such instruction be made in common schools, that a very great reduction in price will be the conse, quence.

Philosophical instruments are not essentially more expensive than tools for tradesmen, or utensils for domestic use. They are dear because the demand is small; but if made in large quantities they will, according to the common results and experience in other matters of trade, be made more cheaply.

I have received, with reference to the class of prizes already alluded to, a synopsis of what is called a knowledge of common things. It is inserted here with the permission of the promoters, and is a good outline of the practical

* The Treasury Minute establishing this department of the Board of Trade, says:-"My Lords concur in the views expressed by the Lords of Committee of Trade, that every means should be used to render these institutions as much self-supporting as possible, and that in the plans adopted, that object should always be borne in mind. My Lords adopt this view, not only because they feel it incumbent upon them to confine the public expenditure to the lowest limit, but also because they entertain a belief that the utility of such institutions is great in proportion as they are self-supporting.” This remark applies equally to all our schools; and school managers would do well to aim at this in all possible cases, as a result which their efforts ought to lead to, and in the end attain,

turn which the schoolmaster ought to give to the knowledge he possesses on this subject. It may also, in some measure, direct him in bringing to bear what he knows on his every-day teaching.

A KNOWLEDGE OF COMMON THINGS.

I.-SOURCES OF DOMESTIC HEALTH AND COMFORT.

A— With regard to food. The value of different kinds of food, both vegetable and animal - the kinds best adapted for keeping up the strength of the body, and those fitted for preserving animal heat*—the mixing of different kinds of food so as to give really nutritious food cheaply - the best kinds of food for hard muscular exertion—the diet of young people and of the sick — the value of various kinds of foreign food, such as Indian corn (maize), rice, arrowroot, sago, etc., and the mode of using them separately or of blending them with home products so as to render them nourishing aud palatable—the advantage of variety in food, and the best mode of cultivating a cottage-garden so as to secure a regular succession of crops of vegetables for domestic use without exhausting the soil — the effects of excess in drink and grossness in living.

B— With regard to cookery. - The best modes of making common things cheap and palatable—the different modes of boiling beef if soup be required, or if it be wanted as boiled beef- the relative advantages of boiling, roasting, stewing, and baking—the best forms of fire-places, stoves, ovens, boilers, etc., for domestic use the baking of bread, etc.

C— With regard to the healthy state of a house. The cheapest and most effectual mode of draining, warming and ventilating the houses of the poor -- the importance of avoiding all collections of refuse and decaying matter. The connection of the common diseases of the poor, such as rheumatism, fevers, inflamations, and contagious mala

* See Frontispiece.

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