The K&E slide rule shown below used its extra length to display extra
accuracy. The Picket was simply a standard rule blown up for advertising
and instruction.
Picture of a K&E 4053-5 20" rule. (~107K)
Closeup on the K&E 20" rule (~40K)
Picture of a Picket 4 foot slide rule. (~43K) The HP-25
is shown to indicate scale.
Some straight rules were more complicated and had two or three slides. Some,
like the one shown below were four-sided and had four slides. This rule was
used in the computation of excise taxes and dates to around 1800-1830. This
rule was made out of boxwood with brass inserts and had a satisfying heft
and quality feel.
Picture of a four sided Dring & Fage excise rule. (~58K)
End view of the four sided rule. (~10K)
Sectors were somewhat similar to slide rules but were designed for working
with angles and trigonometry. They pivoted rather than slid. The sector shown
below was made out of ivory with a brass hinge. Like the four-sided rule
above, this sector had brass inserts at heavy use points.
Picture of a Sector. (~114K)
Back to early models contents
Go on to circular slide rules
Back to Basic Instructions and Straight Rules