At last Vince reached home and had his supper, which had been put out for him, and when he had finished, found that the sea air and exercise had made him ravenous.

“I must have something else to eat,” he said to himself, and he was going into the parlour to speak upon this important subject to Mrs Burnet; but as he reached the door he could hear her pleasant voice, and he knew what was going on, though he could not see through the panels. For the picture rose plainly before his mind’s eye of his father lying back in his easy chair, tired out with his round of the island and gardening, while by the light of a pair of mould candles—

What? You don’t know what mould candles are? The happier you! People did fifty years ago, and they were largely used by those who could not afford wax or spermaceti; and they did what Vince heard the Doctor do from time to time—took up the old-fashioned, scissor-like snuffers from their plated tray, snuffed the candles, and laid them back with a sharp click. And let me tell you that there was an art in snuffing a candle which required practice and a steady hand. For if you of the present generation of boys who live in the days of gas, electric lights, spirit lamps, and candles ingeniously made after the analytical experiments of chemists on a material very different from the old-fashioned Russian tallow—if you, I say, were to try and snuff an old candle, the chances are that you would either cut the cotton wick too much or too little, if you did not snuff the light out. After a time these sources of light would grow lengthy of black, burnt wick, a curious mushroomy, sooty portion would grow on the top, and the flame of the candle would become dull yellow and smoky. Then, if you cut too little off, the light would not be much improved; if you cut too low down, it was worse; if lower still, you put the light out. But the skilful hand every few minutes cut to the happy medium, as the Doctor did, and the light burned up fairly white and clear; so that, according to the custom at the cottage, Mrs Burnet could see well to continue reading aloud to her weary husband, this being his one great enjoyment in the calm life on the island.

Now, it seems rather hard on Vince to keep him waiting hungrily at the door while the writer of this little history of boy life runs away from his narrative to begin prattling in print about candles; but what has preceded these lines on light, and the allusion to chemistry, does ask for a little explanation, for many of you who read will say, What can chemistry have to do with tallow candles?

A great deal. I daresay you have read a little chemistry, or heard lectures thereon. Many of you may have been bitten by the desire to try a little yourselves, as I was, and tried making hydrogen and oxygen gases, burning phosphorus, watch-spring and sulphur in the latter; and even tried to turn the salts of metals back into the metals themselves. But that by the way. Let us return to the candle—such a one as Vince had left burning, smoking and smelling unpleasantly, in the flat brass candlestick upon the little hall table, for it was time he was off to bed. Now, the chemists took the candle, and pulled it to pieces, just as the candle-makers took the loose, fluffy cotton wick metaphorically to pieces, and constructed another by plaiting the cotton strands together and making a thin, light wick, which, as it burned, had a tendency to curl over to the side of the conical flame where the point of the wick touched the air and burned more freely—so freely, in fact, from getting more oxygen from the air than the other part, as to burn all away, and never need snuffing. That is the kind of wick you use in your candles to-day; and the snuffers have gone into curiosity cases in museums along with the clumsy tinder-boxes of the past.

But that is to do with the wick, though I daresay some chemist or student of combustion gave the first hint to the maker about how to contrive the burning away of the unpleasant snuff.

Let us go back to the candle itself, or rather to the tallow of which it was made.

Now, your analytical chemist is about the most inquisitive person under the sun. Bluebeard’s wife was a baby to him. Why, your A C would have pulled the Blue Chamber all to bits, and the key too, so as to see what they were made of. He is always taking something to pieces. For instance, quite lately gas tar was gas tar, and we knew that it was black and sticky, good for palings and horribly bad for our clothes, when, on hot, sunny days, we climbed over the said palings. But, all at once, the A C took gas tar in hand to see what it was made of, and the result is—what? I must not keep Vince and you waiting to tell all—in fact, I don’t know, but may suggest a little. Gas tar now means brilliant aniline dyes, and sweet scents, and flavours that we cannot tell from pears and almonds, and ammonia and carbolic preparations good for the destruction of disease germs. But when the A C attacked the tallow of the candle he astonished us more.

For, so to speak, he took the tallow, and he said to himself, Now, here’s tallow—an unpleasant animal fat: let’s see what it is made of.

Years ago I should have at once told him that it was grease, obtained by melting down the soft parts of an animal. But the A C would have said to me: Exactly; but what is the grease made of?