326 SmoJce-Bings of Vesuvius. 



SMOKE-KINGS OF VESUVIUS. 



BY CHARLES CH. BLACK, M.A. 



Haying read with pleasure the disquisition on Smoke Rings in 

 No. 16 of The Intellectual Observer, I have thought that 

 your readers might be interested in an account of the produc- 

 tion of these phenomena on a large scale. In the years 1845- 

 46, I lived in a villa on the hill of the Infrascata, at Naples, 

 from "which a full view of Mount Vesuvius was obtained. My 

 attention had been often drawn to a curious effect in the con- 

 stantly issuing volume of smoke, resembling somewhat the 

 pine-tree spoken of by Pliny in his well-known description of 

 the aw fill eruption of a.d. 79, but much more regular and 

 gentle, so to speak, than that fearful crest of vapour. This 

 was simply a thin perpendicular stem crowned by an expanded 

 disc, b} r no means unlike the " umbrella pine" of Italy, so 

 often used in Turner's foregrounds, but more aptly typified as 

 to proportion by the trivial comparison of a juggler's soup- 

 plate balanced on a long pole. This appearance, so far as I 

 could judge, was never manifested but in a perfectly calm 

 atmosphere, oftenest in the stillness of summer dawn, when I 

 have seen as many as three or four of these smoke stems suc- 

 cessively disengaged from the volcano's mouth, sailing slowly 

 landwards, and gradually disappearing in the cloudless sky. 

 These discs I afterwards discovered to be smoke-rings, essen- 

 tially similar in their formation to those produced either from 

 a cigar, a cannon, or from chemical apparatus, and having a 

 mechanic action precisely similar to that so accurately described 

 by your correspondent. Seen from a distance of five or six 

 miles, and a height of several hundred feet, it is easy to under- 

 stand that they would present the appearance of solid discs, the 

 edge only being visible. My discovery of their real nature 

 happened as follows : — Accompanied by a friend I was in the 

 habit of rambling about the skirts of Vesuvius, frequently 

 ascending to the edge of the crater, and sketching the fantastic 

 masses of lava with which it was gradually and steadily becom- 

 ing filled. On these occasions we were never attended by 

 guides, and once, on a hot July day, when quite alone, being 

 scaled at different points of the crater, we were surprised by a 

 wild noise in the air. The sound was not unlike that of 

 a steam -whistle, but louder and less regular, dying away 

 gradually directly above our heads. We naturally looked for 

 explanation towards bhe centre of action ', nor were we long dis- 

 appointed. The mouth of the volcano had for weeks, nay months, 

 thrown out with extreme regularity a small jet of stones every 



