Musschenbroek held in one hand this jar, while with the other he attempted to draw sparks from the barrel.

Suddenly he received a shock in the hand holding the jar, that "shook him like a stroke of lightning," and for a moment made him believe that "he was done for." Continuing his experiments, nevertheless, he found that if the jar were placed on a piece of metal on the table, a shock would be received by touching this piece of metal with one hand and touching the wire with the other--that is, a path was made for the electrical discharge through the body.

This was practically the same experiment as made by Von Kleist with his bottle and nail, but carried one step farther, as it showed that the "jar" need not necessarily be held in the hand, as believed by Von Kleist.

Further experiments, continued by many philosophers at the time, revealed what Von Kleist had already pointed out, that the electrified jar remained charged for some time.
Soon after this Daniel Gralath, wishing to obtain stronger discharges than could be had from a single Leyden jar, conceived the idea of combining several jars, thus for the first time grouping the generators in a "battery" which produced a discharge strong enough to kill birds and small animals.

He also attempted to measure the strength of the discharges, but soon gave it up in despair, and the solution of this problem was left for late nineteenth-century scientists.
The advent of the Leyden jar, which made it possible to produce strong electrical discharges from a small and comparatively simple device, was followed by more spectacular demonstrations of various kinds all over Europe.