Doug Kerr
Well-known member
Here we see the classical bowl of (artificial) vegetables, garnished with some artifacts of a family's professional work.
The slide rule to the rear is a Keuffel & Esser Model N4053-3, the Polyphase Mannheim model, made (as near as I can ascertain from its design details and serial number) in 1943.
It belonged to my father, William John Kerr. He was not an engineer by formal training, but was by practical experience. He was involved in the manufacture of (large) custom production machinery, with the same firm from the time of my birth until his retirement (as Vice President of Manufacturing).
This slide rule is made of mahogany with a cellulose acetate ("celluloid") overlay. The cursor runners have disintegrated, but it is in otherwise excellent condition, and operates very smoothly.
It was this slide rule that my father used to instruct me in the operation of a slide rule (perhaps at about age 10).
It has on it a bunch of little hand-scribed index marks my father added. They represent constants he needed for calculations he often made, such as the weight of a large steel roller of certain dimensions, or the weight of a coil of steel sheet, or the gear ratios needed for proper synchronization of the stages of of a cold roll forming mill.
The slide rule in the front is a Keuffel & Esser model N4083-3, the Log-Log Duplex Vector model. It was made in about 1953. It was bought for me by my father on the occasion of my entry that year into Case Institute of Technology (now part of Case Western Reserve University) to take my Bachelor of Science degree in Electrical Engineering.
Like the other K&E rule, it is mahogany with a cellulose acetate overlay.
In engineering schools in those days, the big ideological dichotomy (like PC vs. Mac today) was Keuffel & Esser vs Pickett & Eckel slide rules. The Pickett & Eckel slide rules were made of aluminum (at one time, they had used magnesium) with a white (or sometimes yellow) finish whose nature I do not know. They were thought to be more "modern", would supposedly last forever without warping, not like that dumb mahogany, and so forth. But the drag on the sliding motion could not be finely controlled, and they often made an embarrassing squeak as the slide was moved.
Besides, being metallic, they were "cold". It was, for example, considered bad form to stroke a young lady's breast with one. Of course at Case that was a wholly hypothetical premise for any instrument, since there were no women at all in the undergraduate school (and only a couple in the graduate school at any given time, and one would hardly - well, never mind).
The slide rule is in essentially perfect condition, and operates with a silky smoothness.
The graph paper is a special kind, "reactance paper". It has a system of vertical, horizontal, and diagonal logarithmic axes so that one could readily determine, graphically, the reactance of an inductive or capacitive circuit element at any given frequency (and also make vector reckonings using impedance vectors whose reactive part had been determined on the chart).
I probably got this sheet early in my association with Bell Telephone Laboratories, likely in 1959. The paper was made for them, interestingly enough, by Keuffel & Esser.
For many years after I had any reason to use this, I kept a folder of it in my file cabinet (because it was "so nice"). When we had the big purge of "excess stuff" late in 2007, preparatory to moving to Weatherford from East Dallas, I threw all that out (along with lots of other kinds of graph paper, engineering drawing "format paper", and other pre-CAD artifacts).
But somehow I remembered that a single sheet of it, folded up, had been for many decades in a little brown box of small capacitors in my retained inventory, and I retrieved it to put in this shot.
The slide rule to the rear is a Keuffel & Esser Model N4053-3, the Polyphase Mannheim model, made (as near as I can ascertain from its design details and serial number) in 1943.
It belonged to my father, William John Kerr. He was not an engineer by formal training, but was by practical experience. He was involved in the manufacture of (large) custom production machinery, with the same firm from the time of my birth until his retirement (as Vice President of Manufacturing).
This slide rule is made of mahogany with a cellulose acetate ("celluloid") overlay. The cursor runners have disintegrated, but it is in otherwise excellent condition, and operates very smoothly.
It was this slide rule that my father used to instruct me in the operation of a slide rule (perhaps at about age 10).
It has on it a bunch of little hand-scribed index marks my father added. They represent constants he needed for calculations he often made, such as the weight of a large steel roller of certain dimensions, or the weight of a coil of steel sheet, or the gear ratios needed for proper synchronization of the stages of of a cold roll forming mill.
The slide rule in the front is a Keuffel & Esser model N4083-3, the Log-Log Duplex Vector model. It was made in about 1953. It was bought for me by my father on the occasion of my entry that year into Case Institute of Technology (now part of Case Western Reserve University) to take my Bachelor of Science degree in Electrical Engineering.
Like the other K&E rule, it is mahogany with a cellulose acetate overlay.
In engineering schools in those days, the big ideological dichotomy (like PC vs. Mac today) was Keuffel & Esser vs Pickett & Eckel slide rules. The Pickett & Eckel slide rules were made of aluminum (at one time, they had used magnesium) with a white (or sometimes yellow) finish whose nature I do not know. They were thought to be more "modern", would supposedly last forever without warping, not like that dumb mahogany, and so forth. But the drag on the sliding motion could not be finely controlled, and they often made an embarrassing squeak as the slide was moved.
Besides, being metallic, they were "cold". It was, for example, considered bad form to stroke a young lady's breast with one. Of course at Case that was a wholly hypothetical premise for any instrument, since there were no women at all in the undergraduate school (and only a couple in the graduate school at any given time, and one would hardly - well, never mind).
The slide rule is in essentially perfect condition, and operates with a silky smoothness.
The graph paper is a special kind, "reactance paper". It has a system of vertical, horizontal, and diagonal logarithmic axes so that one could readily determine, graphically, the reactance of an inductive or capacitive circuit element at any given frequency (and also make vector reckonings using impedance vectors whose reactive part had been determined on the chart).
I probably got this sheet early in my association with Bell Telephone Laboratories, likely in 1959. The paper was made for them, interestingly enough, by Keuffel & Esser.
For many years after I had any reason to use this, I kept a folder of it in my file cabinet (because it was "so nice"). When we had the big purge of "excess stuff" late in 2007, preparatory to moving to Weatherford from East Dallas, I threw all that out (along with lots of other kinds of graph paper, engineering drawing "format paper", and other pre-CAD artifacts).
But somehow I remembered that a single sheet of it, folded up, had been for many decades in a little brown box of small capacitors in my retained inventory, and I retrieved it to put in this shot.
