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was allowed to run into the filter. The filter appeared on the outside like a great square chest; and the inside was divided into parallel compartments, by coarse linen cloth, which was stretched over frames of copper. The liquor was admitted into every alternate cell, and was filtered by passing into the cells on either side, which were empty. The syrup flowed out from the filter a transparent fluid, of a pale straw colour.

They were now conducted to the most remarkable part of the new apparatus, the evaporating pans, in which the water was drawn off from the syrup. These were made with double bottoms, so as to admit steam between the two for heating the syrup; and the pans were covered with domes of copper. These domes communicated with the airpump, the great pistons of which were kept at work by the steam-engine. These served to pump out the air, so as to preserve, as far as possible, a vacuum over the liquid. The perfection of the vacuum was shown by a barometer. The master of the sugar-house informed them that it required one hundred degrees less heat to boil sugar in vacuo than in the ordinary method, and that it was accomplished in less than one-fifth of the time formerly requisite.

After having been evaporated, the heat of the sugar was brought to a certain temperature, at which it was found most disposed to crystallize,

It was then poured into earthen moulds of the orm of a sugar loaf, such as were before described, and in these it was allowed to consolidate. It is then of a tolerably white colour, and is purified for the last time by being washed with a solution of the finest white sugar, which is allowed to filter through it. The top and the bottom of the loaves, as being less pure, are then pared off in a turninglathe, and the loaves are afterwards dried in a stove.

Lucy said, that before she came to the sugar house she had a general idea, from what she had read, and from what her father had told her, that sugar went through several processes of filtering, and boiling, and cooling, and crystallizing, before it could be white; but still she was surprised by seeing the number of the different operations, the size of the vessels, and the power and time necessary. She had not been tired by what she had seen, because she knew beforehand the general purpose, and she had not been puzzled or anxious.

Harry was delighted at seeing that principle, which he had before so clearly understood, carried into practice with success in such great works.

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I hope you will now acknowledge,” said he to Lucy, "that the air-pump is of some use in common life, and I hope you are convinced now that the air-pump is almost as useful as the waterpump."

Lucy acknowledged this; and said that Harry might well triumph for the air-pump.

"Think," said Harry, " of its being applied to *such different things as making sugar and making ice; and not only employed for boiling quickly, but for freezing quickly. I do not think that Otto Guerick, or Mr. Boyle himself, could have foreseen all the uses that were to be made of their own inventions. I wish they could see all we have been shown this morning."

"So do I," said Lucy; "I wish they could.” "All goes back to that one great principle of the vacuum," said Harry.

The gentleman who had shown them this establishment, and who had, with the greatest patience and politeness, explained every part of the business, was glad to perceive that he had given pleasure to the young people, and that they had attended to and understood what they had seen and heard. He begged that they would rest themselves before they went away, and showed them into a room, where they found refreshments were prepared. He gave a cup of chocolate to Lucy, and another to Harry.

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You must," said he, "taste some of the sugar, which has been refined by the process you have just seen."

It was in a black Wedgwood-ware basin, which showed its whiteness.

"But, father," cried Harry, eagerly, "can you tell me who invented the method of applying the air-pump so beautifully to this use?"

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"I can tell you," said his father; “it was the invention of Edward Howard, brother to the Duke of Norfolk; he was an honour to his family; and I hope," addressing himself to the master of the sugar-house," that he has been amply rewarded for his ingenuity by the gentlemen of your profession."

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The fruits have been ample," said the master, "but he did not himself reap them; they are enjoyed by his family. He only just lived to per fect his invention."

The master of the sugar-house then entered into a statement of the prodigious quantity of sugar saved by adopting the new process. Eight pounds of sugar, he said, were saved in each hundred weight; and he helped Harry to make a calculation of what that amounted to every year upon the total quantity of sugar refined in Great Britain.

Our party, having finished their chocolate, thanked their host for his attention, and took their leave of him.

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GLASS-HOUSE.

As you go down the hill from Clifton to Bristol, you may see in the city below a number of very high, black-looking buildings, in the shape of huge cones, from which still darker-coloured smoke, in thick black billows, is continually issuing. Some of these conical shaped buildings are glass-houses. Lucy remembered her father's having showed her and told her of what glass is made. She recollected the taste of the alkali, of the ashes of weeds, and the touch and sight of the sand. She recollected also the story of the accident by which it is said the making of glass was first discovered; and, above all, she remembered the pleasure that Harry and she had had in seeing the thermometer man blowing tubes, and bulbs of glass, with his blowpipe. She wished very much to see some more glass-blowing. Her father took her and her brother one day to a glass-house.. Her first feeling on entering the glass-house was surprise at the great heat of the furnaces in which the glass was melted, and pity for the men who were obliged to work close to them. But, when

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