Laser levels - why not just use a ball of string?
In uk.d-i-y, Douglas de Lacey wrote:
wrote:
Laser levels - why not just use string?
"There is no force, however great,
Can stretch a cord, however fine,
Into a horizontal line,
Which is accurately straight"
(W Whewell, Elementary Treatise on Mechanics 1st ed, p 44).
Douglas de Lacey
Surely a line can be perfectly straight or perfectly horizontal, but not
both. Except for a zero-length line, of course.
--
Mike Barnes
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