In the sixteenth century, leech pots are usually presented in the form of glass jars. The pots subsequently became mainly tin even though glass remained a frequently used material. In the nineteenth century, the leeches' pot essentially takes two forms. The French form is that of tin rice bowl: indeed, in the Art published in pewterer 1788 found an engraving reproduced by PA Salmon, showing a rice bowl - a household item produced by pewterers. It is an ovoid object surmounted by a screw cap. A series of holes drilled in the upper third of the sphere passes through its circumference. The lid, which is welded a ring engages, is provided with holes arranged in a circle.
The text specifies Salmon use: "... rice bowl, able to cook in the pot rice or peas, or even vermicelli ". In the book of Father Bidault, medical and pharmaceutical Etains, published in 1972, in the History and art pharmaceutical 10/16 rice bowl exchange definition and becomes a leech bowl. The author provides no indication on sources or the arguments that led to redefine the object. The leech officinale is a robust worm, resistant to cold and frost, undemanding oxygen. The rice bowl with its hermetic closure prevents the escape of animals and has sufficient ventilation holes to keep in some to life. It is a common household item, compact, easy to carry, available among nurses and well suited to this new function. However, this rice ball does not appear, at the time, in the Manufacturers' catalogs medical. Earthenware pots, Products at the time of inflation leeches accurately represent the form rice balls with the same screw cap and vent holes disposed in the same manner body.
The inscription "leeches", noted on some of them proves their use. The second form, Anglo-Saxon is that of English pewterers, which ignore the rice ball and produce "leech" carriers, boxes rectangular tin lid with holes, to store and transport animals. There is, from these two classic forms, many variations. The decorations, sometimes very simple, are often embellished with rich and beautiful colors. There are also non-standard models. For example, the next pot, described by Mr. Blache commissairepriseur and Messrs. J. Ph Nicollier and experts, at an auction in Versailles March 4, 1979.: "Very curious pot leeches with a large pot in which cylindrical high between second cylindrical pot drilled on the bottom and halfway up very many holes, finally, a also perforated lid. On the wall, the word "Leeches".