Some Sources for the History of the Dumbbell

This is the C17 dumbbell at Knole (now a National trust property) as it was towards the end of the Nineteenth Century.

Archaeological Journal 1895   (second version) - worth reading

Archaeological Journal 1896 - worth reading

Antiquary 1905   - worth reading

National trust photo 1 http://www.nationaltrustcollections.org.uk/object/129718.76 The dumbbell (same late C19 photo as in Archaeological journal):

National trust photo 2 http://www.nationaltrustcollections.org.uk/object/129718.77  The gallery (clearly contemporary with dumbbell photo):

There are two C18 references to dumbbells of the ringing type:

Joseph Addison writing in The Spectator on 12 July 1711:

For my own part, when I am in town, for want of these opportunities, I exercise my self an hour every morning upon a dumb bell, that is placed in a corner of my room, and pleases me the more because it does every thing I require in the most profound silence.  My landlady and her daughters are so well acquainted with my hours of exercise, that they never come into my room to disturb me while I am ringing.

In 1746, the Gentleman's Magazine published a drawing and description of a dumbbell. 

The interesting thing here is that the exercise is called "ringing" but in a manner that suggests the author made no connection with bellringing

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