VI

The CONTENTS.

Page

4. Attempts to prepare an ink from more durable

materials - - - 396

Sect. VII. Of the dying of woollen black —- 401

1. General observations on the black dye —— 401

2. Black with galls, logwood, and vitriol —— 410

3. Black dye with verdegris —— —- 411

4. Method of dying cloth grey -—- 413

5. The dying of wool black - —- 415

6. Black dye without galls - - 416

7. Black dye from a combination of colours — 420

Sect.VIII.O/ - the dying of silk black - —— 4 22

Sect. IX. she dying of hats black - - — 428

Sect. X. The dying of linen and cotton black - 429

Sect. XI. 'The staining of wood, irory, stones, &c. black 434

1 . Wood - - -- 434

2 . Ivory, horn, bone, Vc. - —— 435

3. Marble - —— —- 43 ^

4. Agate . 437

Sect.XII. Black glass and enamel - —- 441

N

VII.

History of Plasma — — — 443

Sect. I. Of the general properties ofplatina confdered by itself,

or independent of its disposition to unite or not unitewith other bodies - - 449

1 . Description of platina - - 449

2. Substances mixed with native platina — 450

3. Specific gravity of platina - 452

4. Malleability of platina - - 455

5. Platina exposed to the fre in vessels — 456

■ 6 . Platina exposed to the fire in contadl with the

burning fuel - - 464

7. Platina exposed to a burning glass — 465

Sect. II. Of the aSlion of acids on platina - 469

1. Platina with the vitriolic acid - 469

2. Platina with the marine acid - 470

3. Platina with the nitrous acid - 473

4 . Additional