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ALPHABETICAL LIST OF PAPERS
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are usually meant. The highly-glazed surface is more suited for writing, while the rougher side takes the gum for the flap better than a burnished surface. Envelope papers are usually cut at an angle to prevent waste when cutting out blanks for envelopes. Demonstration of the waste involved by the use of square paper can be made by opening an ordinary envelope, and marking it out on an ordinary sheet of paper.
Feather-weight Paper.—A term applied to bulky book papers much in favour for current fiction. The fibre is esparto, beaten quickly, no loading, but little sizing, very little pressure while passing through the machine. The fibre being loose occupies a large space, and the paper is very light for its bulk, hence the term. Usual sizes and weights: double crown 30 to 60 lb., double demy 40 to 70 lb., and quad crown 55 to 120 lb. per ream of 516 sheets.
Filter Papers are used in chemical laboratories to separate substances in suspension from liquids. It is essential that the papers be entirely free from chemicals, and allow liquids to pass freely while retaining suspended matter. All-rag fibre is used, but grey filter papers may contain a proportion of wool fibre. Filter papers are made as blotting papers, and subjected to special treatment to remove all matter that is likely to confuse chemical analyses. Usual size, 24 by 24 inches.
Foil Papers.—Metals reduced to fine powder are dusted upon the paper which has received a coating of adhesive, and when all is dry the surface is highly burnished. Embossed foil papers are passed through special rolls. Used for covering boxes and picture mounts.
Fruit Paper.—Thin papers, similar to tissues in texture, but much lower in quality, used for wrapping fruits—apples, oranges, etc.—before packing. It is found that this isolation justifies the trouble and expense, an increased percentage of sound fruit reaching the market. Some wrappers are printed with the merchant's name and address.
Glazed Boards.—Millboards which are given a very high surface by repeated rolling.
