Lively Lectures
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LIVELY LECTURES. OLD HUMPHREY'S LIVELY LECTURES AXD CHEERFUL C rfAPTERS. L-O ND ON: THE RELIGIOUS TRACT SOCIETY; Instituted I 799. 56, P .\.TERNOSTER ROW; 65, ST. PAUL'S CHURCHYARD; AND 164, PICCADILLY. CONTENTS. .. PAQR LECTURE ON A CANDLE 5 LECTURE ON A TEA-KETTLE 13 LECTURE ON SMOKY CHIMNEYS 22 LECTURE ON ECHOES 30 LECTURE ON BLACK A.ND WHITE 38 LECTURE ON THE PAPYRUS 46 TRADES CARRIED ON BY BIRDS, BEASTS, AND INSECTS 54 HOW MUCH ARE YOU IN DEBT? 60 FIREWORKS 68 'l'RY THE OTHER WAY 76 VILLAGE IDOLS 81 THE SHINING H OUR 90 ®Ih Jttntptrrt!J'~ LIVELY LECTURES AND CHEERFUL CHAPTERS. LECTURE ON A CANDLE. "PLEASE, Uncle Humphrey, you told me that you would, some time, give me a little lecture on a candle." "Well, Edwin, the promised lecture shall now be given, and let me tell you th.at ui~T object in making you well acquainted with common things, is to accustom you to reflect on the things around you. I will not lose time in asking you questions which, 6 OLD HUMPHREY'S after all, I might have to answer myself; but proceed at once to give you as much in formation as I can ab-out a candle." " Thank you, uncle. The other day you were speaking about 'the division of labour/ so we may as well divide it now. You shall do, if you please, all the talking, and I will do all the listening." " A most unequal division, certainly; but we will not quarrel about it. A candle, to speak of it in the plainest way that I can, is a twisted cotton or linen wick, covered over with tallow, or wax, or spermaceti. At one time there were no better candles than strips of wood, or skewers, dipped in fat ; but these must have burned away very fast." "What a sight it would be, to see a party in the parlour, with the room lit up with skewers dipped in fat ! " "True, Edwin; but, when greasy skewer!! were nsed for candles, tere were ·not many .,. l LIVELY LECTURES, 7 parlmu parties. Common candles- are made by dipping the wicks repeatedly into hot tallow. Mould candles are made by passing the wick up a metallic mould, and then pouring in hot tallow. Wax candles are formed by softening wax in warm water, spreading it flat, and then rolling it round a wick. The candles are afterwards rolled between two fl.at boards, and mad~ smooth. Spermaceti candles are made of a waxy substance, obtained from the whale of the southern seas ; and some candles are formed from cocoa-nut oil. I hardly need tell you that the use of a candle is to give light in the absence of the sun ; but now I must proceed to a few particulars, requiring a . ltttle more thought on your part than what I li~ve aheady told you." " I will do all I can to understand." " Though you may know that wax is obtained from bees, that oil is obtained from ani.rnal and ,egebble ubstances, and that 8 OLD H1J.MPHREY':S tallow is the melted fat of animals ; you may not know that oil, tallow, and wax arc principally composed of carbon, (charcoal, lamp-black, or coke,) and hydrogen gas (one of the principal ingredients in water). The heat of the wick, when light~d, brings out from the tallow the carbon and hydro gen ; and the hydrogen mixing with the oxygen (another gas) of the air, produces flame. A little thought will make this much plainer to you." "But where does the tallow go, as the candle buTns ; for it all goes away without anybody seeing it P" "The heat of the flame melts the tallow, which then rises up through the fine tubes of the wick, and is eaten up by the flame, or, more properly, changed or dissolved. The reason why the flame of a candle is hot, is, because it liberates or sets free the _latent heat of the air and the tallow. By latent heat, 1 mean heat that is not perceivable. LIVELY LECTURES. 9 If you take two cold flint stones, and strike them together, you liberate the latent heat · of the stones and the air, and a spark is visible." "How very curious that there should be heat, though we cannot feel it!'' '' The flame of a candle is a very curious object: the lower part of it is of a violet, or blue colour, occasioned by the hydrogen gas; the upper, where the combustion or ~ame is perfect, is yellow ; and the inside of the :flame is hollow; or, rather, it is com posed of vapour not in a state of combus tion. If the candle were large enough, and · you were to convey through a metal tube a bank of England note into the hollow in the middle of the flame, it would not be burned." " I should never expect to see it again." "The flame of a candle points upwards, because the surrounding air, being heated, rises rapidly, and takes the :flame up with A 2 10 01,D FfUl\fl!HREY' S it. ·The upper part of the flame, being more lively, and lighter than the other part, cannot resist the pressure of the surrounding air; it is therefore pressed, or pinched up, into its taper form." " I cannot make out how you discover all these things.'' "A little ·reading, observation, and re flection soon puts us into possession of a great deal of knowledge. There is some philosophy even in puffing out a candle, for if you blow it g~mtly, you rather feed the flame than otherwise, by driving fresh air into it : but if you blow it sufficiently to separate the flame from the wick, it goes out for want of support, or supply." "That never entered my head before." " When you put an extinguisher over a candle, the flame soons burns the oxygen within it, and when that is done the flame goes out for want of more. If you use an 0xtinguisher made of paper, it is just the LIVELY LECTURES. 11 same, for the flame will go out and not burn it." "I should have thought it would have burned it directly." " The smoke of a candle is composed of the small particles that fly off without being perfectly consumed. The reason why a candle requires snuffing is because the heat of the flame is not great enough to hurn the wick. If you leave a common candle burn ing for some time without snuffing it, there i soon a sort of black cauliflower appear ance at the top of it, occasioned by im perfectly burned particles that have not been carried off into the atmosphere in the shape of smoke." "Oh, there is one thing I wanted to ask you. The other night ~fary stuck a pin through a rushlight, and the flame went out when it came to the pin: what was the reason?'' " The pin being metal, and a good con- 12 OLD HUMPHREY'S ductor of heat, robbed the wick of the heat of the :flame; that was the reason. One of our great writers has very prettily said, How far the little candle throws his beams ! So shines a good deed in a naughty world. And now I must leave you by yourself, that you may think over what I have told you about candles." _,,..- ~, LlY:ELY LECTURES. 13 LECTURE ON A TEA-KETTLE. --8¢8:- "UNCLE Hu::\IPHREY, you have given me a lectluo on the candle, I ·wish you would now give me one on the tea-kettle. I have just been into the kitchen, and seen Mary making the water boil in the kettle, ready for tea." "Willingly, Edwin; nor do I think that you have chosen a bad subject, though it may at first appear to be an odd one. There will be, too, this advantage in such a lecture, that, as I can give it you while we have our tea, we shall always have the tea-kettle before u . You will have no objection, I dare say, to my beginning directly." 14- OLD HUMPHREY'S "No; that is just what I should like." " The tea-kettle now simmering by the fire is an article of very general usefulness ; but, though every one is familiar with its appearance and use, very few, in compa rison, at all understand the several points, or particulars, it presents to a thoughtful mind." " ::Mention as many of them as you can, uncle." "First, then, the material of which it is made. It is required to endure the heat of the fire, and is therefore formed of a hard metal that will not melt. Then, as to its size; for, though kettles are made of all sizes, the most useful one holds a consider able quantity of water to supply the tea table. Nor is its shape unimportant; for the water in it must be boiled without being tainted by the smoke, and the kettle must be easy to fill, pleasant to handle, and con ...-enientl-y formed to uour out the water n LIVELY LEGTUR.ES. 15 "' Not one of these thing.s· have I eveT thought of before." " Every one knows, that" before the water boils, it simmers; but how few know what simmering or boiling is, an-d what occasions it." "I do not, I am sure." "The simmering of a tea-kettle is a slight shaking, or trembling, on the surface of the water ; and it is occasioned by the particles of water low down in the kettle being turned into steam by the heat.