They may be classified into the following types:

1. velvet -- for erasing pencil

2. sandpaper -- for erasing typewriter type

3. scrubbing -- for erasing smudges, charcoal, pencil, etc.

4. roll-off -- for cleaning up drawings

5. kneading erasers -- for cleaning pencil, etc., from walls

6. ink erasers and ink eradicators

7. erasing machines

Sources :

Joseph Dixon Crucible Co., Jersey City, N. J. Eagle Pencil Company, Inc., New York City

Eberhard Faber Pencil Co., Brooklyn, N. Y.

Weldon Roberts Rubber Co., Newark, N. J., New York City

Erasing Machines:

Chicago Wheel & Manufacturing Co., Chicago. Charles W. Speidel &> Co., Philadelphia.

Illllll

No. 00 0 1 2 3 4 5 6 7N 8N 9 10 12 14

Kcuflrl S Esser Co . N<-w York City.

Leroy Let+ering Pens and Width of Letters.

While these pens are designed primarily for use with the scriber and lettering guide shown in 373 they may also be used for free-hand lettering and line drawing. A special socket which fits into an ordinary pen holder is necessary for this.

SUGGESTIONS FOR MAKING A CHART

A good waterproof permanent ink is essential. Colored inks such as red and green are often standard equipment in an office. These may be used to color graphic charts and maps. See 371.

If there is a choice of colored inks, the following order of choice is recommended:

1. black

2. carmine red or scarlet

3. green

4. blue

5. yellow

6. brown

7. orange

KeufTrl H Esscr Co.. New York City.