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Rh between the thickness of the "Encyclopaedia Britannica" printed upon India paper and ordinary printing paper will be fresh in the minds of most readers.

Toned papers are made of the same materials as white paper, the creamy colour being obtained by the addition of a small amount of colouring matter to the pulp.

Featherweight papers are made entirely of esparto, very little sizing is added, no loading is used, the paper is treated so that the wire and felt marks are not easily visible, and the drying and finishing are carried out so as to retain the bulkiness of paper. It must always be remembered that all papers made under such conditions are not durable, and therefore should never be used for work which must withstand any considerable handling.

Coloured and tinted papers are made of the same materials as white printings, but usually the fibres will be chemical wood and esparto, all chemical, or a mixture of chemical and mechanical wood pulps. The variety of tints in which papers can be obtained is very extensive, and this is impressed upon one when trying to match up some particular shade, when it appears as though makers have many substitutes for the desired colour. The colours of papers should be fairly fast to light, and with the large variety obtainable by the use of the pigments and dyes now on the market, paper-makers manage to offer a long range of fast colours. Although it may not always be so, fastness usually follows the price of the paper, the cheapest being the most liable to fade quickly. Delicate tints are more expensive because of the necessity of a better quality of paper to take the colours evenly and cleanly. Coloured printing papers should be fairly well sized, well finished, and free from spots and specks.

In addition to possessing the good qualities of