JF Ptak Science Books  Quick Post

This fantastic image was found in an 1854 article¹ on pre-wireless  ship-to-ship audio communication. The point of the article of course was deadly serious: using a steam-driven whistle not only for signalling to other ships (a la the truncated communication systems between trains on their whistles) but also employing it as a type of RADAR where you may be able to determine what foggy things lay ahead by virtue of their echo, among other things. The article describes the scene below as an effective arrangement for the broadcasting whistle (on the mast or funnel at left) and the “signal-man” in his “pent-house” at left, though I don’t see any instrumentation for the guy. That structure was supposed to shield his hearing from the audio blasts which were to be heard at a distance of five or six miles (and which were to be sounded every few minutes)–the hut seems a little flimsy for that purpose.  In any event, removing the image from its context presents us with something very spare and very creative:

Notes:

1. John C. Cresson, “Remarks upon the Use of Phonic Signals in Navigation”, pp 397-400, in the Journal of the Franklin Institute, Philadelphia, Vol 28 (third series), volume 58 (overall), July-December 1854.