"You forgot that the paper was smeared first with soft soap," said Harry.

1

"Then, when you want to use these patterns," said Lucy, "the superfluous paper is cut off, and the printed part is moistened and laid on the cup, or whatever you wish to put it on.”

"The cup must be in the state of biscuit, remember," said Harry.

"Biscuit, to be sure," said Lucy; "the biscuit instantly sucks in, absorbs the colouring stuff, from the moistened pattern; then the paper is washed off, and you see the coloured pattern printed on the cup directly. Is not that nice and quick, mamma? Then the cup must be let to dry, and afterwards it is dipped in some sort of glazing stuff, and the cobalt, I mean the oxide of cobalt, comes out a beautiful blue. And there is the cup finished, painted in this easy, expeditious way: a hundred thousand, I dare say, could be painted in this manner, while a person could paint one single cup in the old way."

"The name of the ingenious person, as Mr. Frankland said, who discovered this method of transferring engraving from paper to earthenware, has not been preserved, and I am sorry for it," added Harry.

“Mr. Frankland told us, that since this invention, this blue and white ware has been made in such quantities, and so cheap, that now almost every body can afford to buy it, and it is in every cottage; and the poor people can have now, what only the rich and grand had formerly. Are not you very glad of that, mamma?"

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Yes, I am, my dear," said her mother; "and I am glad," added she, smiling, "that you give yourself time to take breath at last, and that you allow me time to thank you for all you have told me. You seem to have been very much entertained at the potteries, and you have entertained me by your account of them."

"Mamma," said Lucy, "do you think we have remembered enough? I know I cannot recollect half what I saw and heard,

but I remember almost all that I under

stood clearly."

"That is quite enough, my dear," said her mother; "I never wish you to remember more than you understand. Of what use could it be?"

"GOOD morning to you, mamma,” said Lucy. "I forgot to tell you yesterday, when we were talking about the potteries, that we saw the house, in which Mr. Wedgwood formerly lived; and a very nice house it is."

"Good morning to you, father," said Harry. "Do you recollect yesterday seeing a man standing by one of the furnaces measuring some little stoppers of baked clay, which he slid in between two pieces of brass, like the two parts of a hinged ruler. These pieces of brass were fixed, but not parallel to each other; they were closer together at one end than at the other. The man took the bits of clay, or

stoppers, out of a heated furnace, and he tried each stopper between these rules, and looked at divisions, which were marked on the brass plates. What was he doing, papa?"

"He was using a sort of thermometer, Harry," said his father.

"A thermometer of clay, papa!" said Lucy.

"Yes, for measuring higher degrees of heat than can be shown by that thermometer which you have seen; if that were exposed to heat beyond the highest degree marked on its scale, the quicksilver would expand, so as to burst the glass, and the glass would melt, if put into one of those furnaces which you saw yesterday; but these clay thermometers can bear, and can measure the heat of the fire; for which reason it is called a pyrometer, that is, measurer of fire heat."

"I am glad I know the name, and what it means," said Lucy.

"Father," said Harry, "will you be so good as to explain the pyrometer to me??

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Harry, will you be so good as to use your own understanding?" said his father. "From what you have seen, and from what I have just told you, you know enough to comprehend or invent the rest, without any further explanation from me."

Harry was silent, and considered first its use. He had seen the man put the stopper into the furnace, and then measure it between the rulers, and afterwards say to another workman- the man who was feeding the furnace, "This heat will do." Now, thought Harry, what change could have been made in the clay, after it had been put into the furnace, and how did he measure it, when he pushed it in between the two rulers? He must have tried whether it had grown larger or smaller, after having been put into the fire.

"I think," said Harry, "that perhaps some sorts of clay either shrink or grow larger, when they are put into the fire. If they did so always regularly, and if people found this, after a number of trials, then they might know the heat of the fire by