Prism-like vertical icicle growing from a birdbath in Sussex, December 21, 1992.
The British journal Weather has published two more photos of upside-down icicles. We reproduce one that is typical of the genre. [Another growing at an angle from a birdbath is sketched on SF#79.] In the formation of such icicles, liquid water is somehow forced upward from a reservoir through a central channel. As it reaches the top, it freezes. If this is indeed the mechanism, why do these upside-down icicles usually form crystal-like prisms with flat sides?
Delightfully, the plot becomes more twisted with a beautiful horizontal helical icicle that was photographed in New Zealand. This truly strange icicle looks like a horizontal bedspring 6 inches long and 2 inches wide. There are eight complete turns in the helix. It has grown several times from a hairline crack in a handrail support which fills with water during a rainstorm.
(Dowden, Richard, et al; "Helical Icicle," Weather, 49:435, 1994.)
"Before opening the book, I set certain standards that a volume which treads into dangerous grounds grounds like this must meet. The author scrupulously met, or even exceeded those standards. Each phenomenon is exhaustively documented, with references to scientific journals [..] and extensive quotations" -- "Book Review: The moon and planets: a catalog of astronomical anomalies", The Sourcebook Project, 1985., Corliss, W. R., Journal of the Royal Astronomical Society of Canada>, Vol. 81, no. 1 (1987), p. 24., 02/1987
