Seed Merchants, Swainseeds, JS Ltd. Seal 
JS Ltd. Seal, Image by StuE, Found by Doug Turner. 
Found in Somerset, 18mm, 6.0g. 
 
J.S. with LTD. beneath on one side and a double triangle on the other. 
 
This mark is identical to that used by the seed merchants  - Swainseed. Perhaps J. Swain Ltd.?
 
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Size: 
 
Full size: 
 
1175x794
 
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