LEAF-Skeletons. One help for acquiring a knowledge of the anatomy of plants, is the art of reducing leaves to skeletons, which may be done by exposing the leaves to decay for some time soaked in water, by which means the softer will be separated from the internal harder parts. By carefully wiping, pressing, and rinsing them, the harder parts may be obtained from the rest alone and entire. Some have been able to separate the outer covering on both sides from the woody net, and even to split the latter into two. A naturalist in the year 1645 first conceived the idea of making leaf-skeletons by employing decomposition for that purpose, assisting it by several ingenious operations of art. When the method of producing these skeletons was publicly known, numberless preparations of them were everywhere attempted. So much did leaf-skeletons afterwards engage the attention of philosophers, that one Seligmann wrote a treatise on the various methods which may be employed in their preparation.
The art also of raising trees from leaves has been long known, the first account of which was published by Agostino Mandirola, an Italian of the Franciscan order, who assures us that he produced trees from the leaves of the cedar and lemon tree. In the garden of Baron de Munchausen, a young tree was obtained from a leaf of the limon à Rivo, which yielded fruit the second year: It is more than probable that the multiplication of the opuntia or Indian fig, first suggested the idea of such experiments, for every joint of that plant when stuck into the earth, and properly nurtured, throws out roots and grows.