Franklin lightning engraving

The accompanying text reads:

Who first took lightning from the clouds?—Dr. Franklin first drew electricity from the clouds in such a way as to be able to examine it, and prove that lightning is nothing but electricity.

How did he do it?—This discovery of the nature of lightning was one of the most important ever made in science, and yet, Dr. Franklin made it simply by flying a kite in a thunder-shower (Fig. 82).
He made his kite of silk instead of paper, and sent it up with a hempen cord ending in a piece of silk cord, by which the kite was held. It is said that he fastened a doorkey to the lower end of the hempen cord, and that after his kite had been for some time sailing among the clouds he touched the key with his knuckle and drew a spark of electricity from it. The electricity in the cloud entered the kite, and came down the hempen string to the key, but could not go any farther because the silk cord was not a conductor. When the doctor presented his hand the electricity in the key leaped into his knuckle.