True, the yard changed size in 1893 and then changed size back again,
nearly to the size of the bronze yard you cite. Nonetheless, those were
measurable changes, even measurable by methods of the time. Mendenhall
knew he was rounding off to the nearest part in just under 4000, for
instance.
More significantly, the size of the meter never was changed from its
"prototype" size, despite changes in definition.* All those changes
maintained the size within the capabilities of metrology as they existed
at the time of the changes. A purist would say, "yes, the meter did
change size with each definition change -- but we just couldn't measure
that change nor its direction."
The difference of course is that the 1893 and 1959 changes in size of
the yard occurred because of redefinition in terms of two mathematically
disernably different fractions: 3600/3937 and 0.9144.
I grant you, those changes were small. But the 1959 change was
sufficient to move Congress to define a separate "survey foot" and thus
a different "statute mile" based on that survey foot. Those are
mathematically and physically different in size from the 1959
international foot (one-third yard, actually) and international foot.
Jim
* The only change in size was between the temporary meter, which was
used for a brief time pending completion of the Barcelona-Dunkirk
survey, and the prototype meter. Most folks misunderstand the meaning of
"prototype" and think it synonymous with "temporary".
--
James R. Frysinger
632 Stoney Point Mountain Road
Doyle TN 38559-3030
(C) 931.212.0267
(H) 931.657.3107
(F) 931.657.3108
On 2014-05-13 16:30, John M. Steele wrote:
I used to point out both changes too. However, careful reading of SP
447 shows that old bronze yard #11, the official physical standard
before Mendenhall, when compared to the modern 0.9144 m yard, had less
than 0.1 X of the discrepancy of Mendenhall yard 3600/3937 m.
If Mendenhall had done it right, we wouldn't have needed the 1959
agreement. The 1893 declared value was an unfortunate choice and they
knew better at the time.
------------------------------------------------------------------------
*From:* James <[email protected]>
*To:* U.S. Metric Association <[email protected]>
*Sent:* Tuesday, May 13, 2014 4:01 PM
*Subject:* [USMA:53811] RE: Archaic units persist
I make fun of them too, Martin! My biggest hope is to make the unending
debate about what to call the hodgepodge of units used here a moot
issue
by going entirely SI in the US. I take great delight in pointing out to
folks that my grandpa's yard stick is no longer valid since the size of
the yard (and inch, foot, etc.) in the US changed size in 1959. And
that
it had also changed size in 1893.
Jim
On 2014-05-13 14:45, Martin Vlietstra wrote:
> Not to worry Jim, You should know by now that I take every
opportunity to
> ridicule the difference between Customary and Imperial units,
especially
> when the same name means different things depending on which side
of the
> "pond" you are.
>
> Martin
>
> -----Original Message-----
> From: [email protected] <mailto:[email protected]>
[mailto:[email protected] <mailto:[email protected]>]
On Behalf
> Of James
> Sent: 13 May 2014 20:18
> To: U.S. Metric Association
> Subject: [USMA:53809] RE: Archaic units persist
>
> Yes, those naturally were US units of measure (esp. the gallon)
since I went
> to school in the US. Perhaps I should have made that statement
explicitly.
>
> Jim
>
>
> On 2014-05-13 13:45, Martin Vlietstra wrote:
>> Hi James,
>>
>> I assume of course that I would have to use a little over 3
quarts of
> water.
>> :-)
>>
>> Regards
>>
>> Martin, resident in the UK.
>>
>> -----Original Message-----
>> From: [email protected] <mailto:[email protected]>
[mailto:[email protected] <mailto:[email protected]>] On
>> Behalf Of James
>> Sent: 13 May 2014 18:19
>> To: U.S. Metric Association
>> Subject: [USMA:53807] Archaic units persist
>>
>> This article from the Chattanooga Times-Free Press states the total
>> production of the mills owned by a company that is setting up new
>> headquarters in Chattanooga TN:
>>
http://timesfreepress.com/news/2014/may/13/flour-mills-merge-form-chat
>> tanoog
>> a-based-grain-cra/?breakingnews
>> It gives their production in hundredweights (cwt). A hundred
weight is
>> 100 pounds avoirdupois. (In Britain, I believe a hundredweight
was 112
>> lb, or 8 stone.) So, this archaic unit persists in the US.
>>
>> Side story:
>> Years ago I worked my way through college by working
part-time in a
>> campus bake shop. We routinely received our various flours in
100 lb bags.
>> The male permanent baker (not a student, such as I) and I got into a
>> contest on hauling bags of flour from the storeroom. I, at one time,
>> carried a 100 lb bag on each shoulder and one in my arms
simultaneously.
>> I loaded those three bags onto my shoulders and into my arms by
myself.
>> That was back in my youth ... sigh. Of course, I could still do that
>> if I really, really wanted to! But I'm wiser now. (Grin.)
>>
>> I still recall the excellent pie dough recipe we used. It made
25 pie
>> shells. Unfortunately, it's in gallons, pounds, and ounces:
>> 25 lb pastry dough
>> 13 oz salt
>> 10 lb lard
>> 8 lb fine shortening
>> 1 gal water
>> Stir the dry ingredients together. Cut in the fat to form coarse
crumbles.
>> Add the water and mix, taking care not to over mix. Double the
recipe
>> to make 25 "lids" for the pies.
>>
>>
>> Jim
>>
>> --
>> James R. Frysinger
>> 632 Stoney Point Mountain Road
>> Doyle TN 38559-3030
>>
>> (C) 931.212.0267
>> (H) 931.657.3107
>> (F) 931.657.3108
>>
>>
>>
>>
>>
>
>
>
>
>
