58

DYEING AND CALICO PRINTING.

bleach linen than cotton fabrics. Flax fibre being more susceptible of injurythan cotton fibre, a more tedious bleaching process is necessary. It is con-duced in the following manner:—The linen, instead of being steeped in hotor cold alkaline lyes, is first macerated in an infusion of malt at 149° F. (65° C.),after which mixtures of carbonated and caustic alkalies or resin-soap areemployed at temperatures not exceeding 140° F. (6o° C.); these are repeatedafter every washing and maceration. The linen is next exposed to the air ongrass fields, and after the alkaline washings have been frequently repeated aweak solution of bleaching-powder is employed, followed by a sour-bath. It isimpossible for linen to be thoroughly well bleached without frequent exposureto the air, and the expense attending these exposures partly accounts for thehigh price paid for linen as compared with cotton.

Such is the old method of bleaching linen, but later methods have beenintroduced in which the time of exposure on the grass, or “ crofting,” as it istermed, is much shortened. Dr. Ure very fully describes one of theseprocesses as pradtised by an extensive bleacher in Scotland and Ireland, asfollows:—

1. Wash.

2. Boil in lime-water ten or twelve hours.

3. Sour in muriatic acid, of 2° Twaddle, for three, four, or five hours.

4. Wash well.

5. Boil with resin and soda-ash twelve hours.

6. Turn the goods, so that those at the top shall be at the bottom, and boilagain as at No. 5.

7. Wash well.

8. Chemick at Twaddle, or ioo2'5 four hours.

g. Sour, at 2° Twaddle, ioio'o specific gravity.

10. Wash.

11. Boil in soda-ash ten hours.

12. Chemick again.

13. Wash and dry.

Other processes are adopted for sheetings, but, for printing, that quoted maybe considered a fair example. By this process a fortnight is consumed inbleaching the goods. The continental processes are even still more tedious,occupying generally a period of six weeks.

White Bleaching Linen Yarn.

On the small scale the yarn may be boiled in a lye of soda-ash, or better,caustic soda, for about five or six hours ; then taken out and rinsed ; passedthrough a bath of chemick, when it will assume an egg-yellow shade. Thenit must be rinsed, and crofted, or spread on the grass exposed to the sunlight;and if it is often wetted with water and turned it will become perfectly whitein a few days.

Colouring Linen Yam for Carpets on the Small Scale.

Coarse yarn is largely employed in the manufadture of special classes ofcarpets, and we append to the consideration of linen and its modes ofbleaching some pradtical formulae for the colouring of the yarn.

The yarn for blue, red, yellow, green, lilac, and aniline colours ought to