Origin of "beat" as a census division?

In one sense, the word beat means an area regularly traversed by someone, such as a police officer. I'm wondering about the origin of this term as applied to an obsolete type of census division in some southern states, such as Mississippi. Specifically, were these simply existing police beats adopted for the purposes of enumeration? Or did the Census Bureau devise its own precincts based on the same sense of the word—i.e., an area that might be traversed or canvassed by a particular census-taker?

There's some evidence for the former, as genealogy web sites refer to subdivisions called "police districts" at around the same time; some even explicitly mention "police beats", but they may be applying the term conjecturally. And still today, police beats are used for certain types of record-keeping, such as crime statistics. But is there any history of the term beat being used for an enumeration district, separate from the context of a police beat?

Solution 1:

The OED acknowledges this as definition 10.d.:

d. ‘In Alabama and Mississippi, the principal subdivision of a county; a voting-precinct’ ( Cent. Dict. 1889).

The earliest attestation is from 1860 and uses the word alternated with "precinct."

Governor Holmes appointed me..commissioner to take the census and organize beats or precincts.

• 1860 J. F. H. Claiborne Life & Times Gen. Sam. Dale x. 166

As for etymology, the OED offers no notes apart from the attribution to The Century Dictionary first edition.

The full text of that edition was made available by the University of Toronto, and the relevant entry for beat can be viewed here.

4. A round or course which is frequently gone over: as, a watchman's beat; a milkman's beat...

Hence — 5. A course habitually traversed, or a place to which one habitually or frequently resorts. — 6. In Alabama and Mississippi, the principal subdivision of a county; a voting precinct.

It appears from the dictionaries that the census use was an outgrowth of the "police beat" use, but one specific to Alabama and Mississippi. The OED, as mentioned earlier, placed this definition under 10., which contains definitions referring to a course or area often traversed, and it cites earlier dates referring to a watchman's beat.

The word "Hence" used by Century Dictionary seems to be a similar acknowledgment that its definitions 5 and 6 grew out of 4.

Although the OED offers an 1860 citation, the term can be found earlier in public notices.

• 1853 - The Sumter Democrat (Livingston, AL) 23 Apr 1853 2/2 (paywall)

Solution 2:

etymonline.com says the meaning of a "regular route travelled by someone" dates to 1731. I don't know if policemen of that time had regular routes like they do in more modern times. It seems like the use for police patrols and census taker coverage are just specific cases of this general use. A suggested origin is that it's related to the way their feet beat on the ground as they walk their route.