The two-flue harpoon or two-flue iron (which, together with the one-flue harpoon, were known as common harpoons) is a type of harpoon used in whaling for at least 1000 years. It appears in works of art dating back to the 14th century.
In the early 19th century the design was modified, and the one-flue harpoon was created. By removing half of the point, the chance of the point cutting its way back out of the whale was greatly reduced.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction