To fasten harness together with bits of rope, &c. in a make-shift way. Hence the noun.

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1854.  

        I remember with pleasure my grand-father’s goggles,
  Which rode so majestic astraddle his nose;
And the harness, oft mended with tow-string and ‘toggles,’
  That belonged to old DOLLY, now free from her woes.
Knick. Mag., xliv. 205 (Aug.).    

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