How long can a pencil write

I didn't believe the Pencil Pages when they said that a standard pencil writes 35 miles [1]. It seemed that there's a ring of plagarism going on because Papermate which makes the American brand of pencils also says a pencil writes 35 miles [2]. That's more than an order of magnitude greater than a pen which can only write 1.5 miles [3]. The pen number seems more accurate since Bic has a slightly different number, 2 miles [4].

I decided to test this myself.

• Sharpen the pencil
  
• Mark a pencil, one inch above the point.
  
• Write with the pencil.
  
• See how much the mark moved. This shows how much of the graphite lead was consumed by the writing.
  

Here's the line marking 1 inch from the tip of the pencil.

I used a pen to make two lines 6 inches apart.

I would make lines with a pencil between the pen lines. I counted each of these pencil lines in groups of ten. Here I've drawn 30 lines.

I found that 15 feet (30 pencil lines) of writing uses 1/16th of an inch of graphite.

An unused pencil of mine measures in at just over 6.5 inches.

This means that a pencil can write 1560 feet. Your mileage may vary since people write with different pressures and sharpen their pencils at different intervals.

Sources accessed on Nov. 13, 2006.

[1] http://www.pencils.com/trivia.html

[2] http://www.papermate.com/sanford/consumer/papermate/faqs.jhtml?cat=Pencils&q=0070

[3] http://www.papermate.com/sanford/consumer/papermate/faqs.jhtml?cat=Pens&q=0010

[4] http://www.bicworld.com/inter_us/stationery/faq/index.asp