how to make a pan-hectographic non electric printing press : LUSENET : TimeBomb 2000 (Y2000) Preparation Forum : One Thread

Here's how to make a non-electric printing apparatus that you may remember from grade school. This suggests adding unflavored gelatin, rubbing alcohol

1. Prepare unflavored gelatin and pour into a shallow pan. Allow to cool and solidify.

2. Using a ditto master (available from a teacher supply store), type or write a message.

If you don't have any manufactured ditto masters: Make a coal tar dye by boiling coal (one kilo of coal is enough for thousands of sheets). Paint a sheet of paper with this dye and allow it to dry. Place a second sheet of paper onto the painted paper (with the dye back to back with the blank paper) and type or write your message on it.

3. Separate the second sheet -- which is now a "ditto master" -- and dampen it with alcohol. Press onto the gelatin for about 30 minutes. Peel off.

4. Press blank sheets of paper onto the gelatin, thus duplicating your message. Each ditto master image is good for about 200 copies.

If there are any school teachers out there, now is a good time to contribute your expertise in this kind of duplication ;),

-- robert waldrop (, July 21, 1999


Coal tar can be hazardous to health. Short course in POLYCYCLIC AROMATIC HYDROCARBONS:
CARCINOGENICITY There is sufficient evidence for the carcinogenicity of the following polycyclic aromatic hydrocarbons (PAHs) in experimental animals: benz [a]anthracene (56-55-3), benzo[b]fluoranthene (205- 99-2), benzo[j] fluoranthene (205-82-3), benzo[k]fluoranthene (207- 08-9), benzo[a] pyrene (50-32-8), dibenz[a,h]acridine (226-36-8), dibenz[a,j]acridine (224-42-0), dibenz[a,h]anthracene (53-70-3), 7H-dibenzo[c,g]carbazole (194-59-2), dibenzo[a,e]pyrene (192-65- 4), dibenzo[a,h]pyrene (189- 64-0), dibenzo[a,i]pyrene (189-55-9), dibenzo[a,l]pyrene (191-30-0), indeno[1,2,3-cd]pyrene (193-39-5), and 5-methylchrysene (3697-24-3) (IARC V.3, 1973; IARC V.32, 1987; IARC S.7, 1987).

All 15 PAHs form as a result of incomplete combustion of organic compounds. The primary source of PAHs in air is the incomplete combustion of wood and fuel for residential heating. The PAHs are found in gasoline or diesel motor vehicle exhaust, by-products of open fires or refuse burning, coal tar, coal tar pitch, coke tars or coke oven emissions, creosote, mineral oils, bitumens, industrial smoke and soot, cigarette and cigar tobacco and smoke, tar, or smoke condensates, and charcoal-broiled foods.

Health Effects of Coal Tar Pitch Volatiles (CPTV's)

Unprotected workers early in this century who were exposed to CTPV-like chemicals in several professions developed lung, bladder, skin and kidney cancers at rates higher than workers not exposed to CTPV-like chemicals. It has been shown that long-term exposure to high levels of CTPVs can increase lung cancer risks, but no single component of CTPVs has been singled out as the lone culprit. Benzo(a)pyrene, however, is one of the known carcinogens and therefore is used as a "fingerprint" for the presence of potentially harmful chemicals.

CTPVs may irritate the skin and breathing passage. Chronic bronchitis may also develop from contact. Coal tar photosynthetically changes in sunlight and when it contacts the skin in the presence of sunlight it may cause irritation that takes the form of redness resembling a bad sunburn.

Where CTPVs are present as gases, they may irritate eyes, especially in comb ination with sunlight. Scientific evidence suggests that direct eye contact with coal tar can lead to temporary or permanent eye damage.

(My emphases.) Only prolonged exposure to CPTV's carries these health risks. Nevertheless...

-- Tom Carey (, July 22, 1999.

I made one of those many years ago. I remember that the ratio of water to gelatin was changed. Use much less water than usual so that the result is very stiff. Marianne

-- Marianne (, July 22, 1999.

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