| 880 | gr. | water. |
| 100 | „ | pure hydrochloric (muriatic) acid. |
| 20 | „ | potassium chlorate. |
CHAPTER VII.
RECOMMENDATIONS AND AUXILIARY PROCESSES.—ZINK AND STEEL PLATES.—VARIOUS THEORIES.
A. Recommendations and Auxiliary Processes.
73. The Roulette.—The latitude which I gave you does not extend to the point of approving of all material resources without any exception. There is one which I shall not permit you to make use of, as the needle has enough resources of its own to be able to do without it. I allude to the roulette, which finds its natural application in other species of engraving.
74. The Flat Point.—Employ the flat point with judgment; it takes up a great deal of varnish, but gives lines of little depth, and of less strength than those which can be obtained by prolonged biting, with an ordinary needle.
75. The Graver or Burin.—“And the graver: what do you say to that?”