A Brief History of Signals

Prior to the advent of practical electrical communication, human beings had been signaling over a distance in all kinds of ways. The bell in the church tower called people to religious services or “for whom the bell tolls”—the announcement of a death. We knew a priori several things about church bells. We knew approximately when services were to begin, and we knew that a long, slow tolling of the bells announced death. Thus we could distinguish one from the other, namely a call to relig...

 Things Discovered by Many at the Same Time

It is notorious that the same discovery is frequently made simultaneously and quite independently, by different persons. Thus, to speak of only a few cases in late years, the discoveries of photography, of electric telegraphy, and of the planet Neptune through theoretical calculations, have all their rival claimants. It would seem, that discoveries are usually made when the time is ripe for them—that is to say, when the ideas from which they naturally flow are fermenting in the minds of man...