that he lifts, makes 1000 lib.

But he ought to lift 900 lib.

besides the weight of his body, to be as strong again as a man of 150 lib.-weight who can lift 400 lib.
Now as all men are not proportionably strong in every part, but some are stronger in the arms, some in the legs, and others in the back, according to the work and exercise which they use, we can't judge of a man's strength by lifting only; but a method may be found to compare together the strength of different men in the same parts, and that too without straining the persons who try the experiment.
Here follows a long description of a machine for the above purpose.
Topham was not endowed with a strength of mind equal to the strength of his body.

He was married to a wanton who rendered existence so insupportable that he committed suicide before he was forty years of age, on August 10th, 1749.[1] About the year 1703 there appeared in London a native of Kent, by the name of Joyce, who won the name of a second Samson by a series of feats of strength that to the people of that day seemed little short of superhuman.

Dr.Desaguliers, in his Experimental Philosophy, gives the following account of Joyce and his methods.
About thirty years ago one Joyce,[2] a Kentish man, famous for his great strength (tho' not quite so strong as the King of Poland, by the accounts we have of that Prince) shewed several feats in London and the country, which so much surprised the spectators, that he was by most people called the second Sampson.[3] But tho' the postures which he had learned to put his body into, and found out by practice without any mechanical theory, were such as would make a man of common strength do such feats as would appear surprising to everybody that did not know the advantages of those positions of the body; yet nobody then attempted to draw against horses, or raise great weights, or to do anything in imitation of him; because, as he was very strong in the arms, and grasped those that try'd his strength that way so hard, that they were obliged immediately to desire him to desist, his other feats (wherein his manner of acting was chiefly owing to the mechanical advantages gained by the position of his body) were entirely attributed to his extraordinary strength.
But when he had gone out of England, or had ceased to shew his performances, for eight or ten years; men of ordinary strength found out the way of making such advantage of the same postures as Joyce had put himself into, as to pass for men of more than common strength, by drawing against horses, breaking ropes, lifting vast weights, &c.