Hello all
Two sightings:
1. Brenda Maddox, "Rosalind Franklin, the dark lady of DNA" has a
photograph Watson and Crick and the 1953 model of the DNA. The caption says
"...For the purpose of the picture, Crick was persuaded to point with a
slide rule even though he had not used one in preparing the model".
2. The March 2003 edition of 'Physics Today', page 13 has a story about
Fermi by Albert Bartlett. Fermi drew x and y axis on a chalkboard and then
drew a curve. The axis and the curve had no quantitative markings. "...He
then stepped back from the board, thought for a moment, took a six-inch
slide rule from his shirt pocket, and did a quick calculation. The result of
the calculation prompted him to to say that the level part of the curve was
not as high as he had drawn it. Going backto the board, he used his fingers
to erase the horizontal part of the curve and then carefully redraw it an
inch or two lower than it had been initially. The room was silent for a
moment, and then laughter erupted. Fermi smiled and continued the lecture".
Regards
Pearu Terts
-----Original Message-----
From:
kayjohn6@... <
kayjohn6@...>
To:
sliderule@yahoogroups.com <
sliderule@yahoogroups.com>
Date: Monday, 6 January 2003 22:30
Subject: SR Vector Scales
>All,
> After perusing Clark McCoy's fascinating K&E slide rule catalogs, and
with
>my "new" 4093 Log Log Vector, I have a question about Vector rules:
> As far as I can tell, K&E brought out the 4093 Log Log Vector slide rule
in
>1930. The vector designation for this rule is associated with two
>characteristics: a double set of trig scales, one inverted on the slide
>making right angle solution very convenient, and a set of hyperbolic
scales.
>In the catalog, they tout the usefulness of using these scales for solving
>right triangles, and oh by the way they also have hyperbolic scales that
>electrical engineers would find useful.
> The 4093 was superseded by the 4083 Log Log Duplex Vector (though I once
saw
>an ebay listing with 68-series numbers that looked like the 4093 scale set,
>so two scale sets may have coexisted for quite a while). With the 4083,
>however, the trig scales are identical to the 4081 Log Log Duplex Decitrig,
>but it has hyperbolic scales. At this point, "vector" appears to refer
>exclusively to hyperbolic scales, though the catalog continues to mention
>improved solving of right triangles.
> For other slide rules (Picket, Lafayette), the "Vector" designation is
>associated solely with the hyperbolic scales. Aristo did not use the
"vector"
>terminology at all, having "Hyperlog" designation. Now for my question:
> Did K&E come up with the "Vector" designation for rules with additional
>trig and hyperbolic scales, or was it someone else? When were hyperbolic
>scales first introduced?
>Cheers,
>John Kay
>
>
>[Non-text portions of this message have been removed]
>
>
>
>
>Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>