Thread:ComicReadingGamer/@comment-26381576-20190412201902/@comment-39119256-20190413081644

History[edit]
The tin canning process was allegedly created by Frenchman Philippe de Girard and the idea passed to British merchant Peter Durand who was used as an agent to patent Girard's idea in 1810.[2]  The canning concept was based on experimental food preservation work in glass containers the year before by the French inventor Nicholas Appert. Durand did not pursue food canning, but, in 1812, sold his patent to two Englishmen, Bryan Donkin and John Hall, who refined the process and product, and set up the world's first commercial canning factory on Southwark Park Road, London. By 1813 they were producing their first tin canned goods for the Royal Navy. By 1820, tin canisters or cans were being used for gunpowder, seeds, and turpentine.

Early tin cans were sealed by soldering with a tin-lead alloy, which could lead to lead poisoning. Infamously, in the 1845 Arctic expedition of Sir John Franklin, crew members suffered from severe lead poisoning which was first thought to be caused by eating tin canned food. More recent research however suggests the lead poisoning was more likely to have been caused by the water pipe system on the two ships.

In 1901 in the United States, the American Can Company was founded, at the time producing 90% of United States tin cans.[3]

Description[edit]
Most cans are right circular cylinders with identical and parallel round tops and bottoms with vertical sides. However, cans for small volumes or particularly-shaped contents, the top and bottom may be rounded-corner rectangles or ovals. Other contents may suit a can that is somewhat conical in shape.

Fabrication of most cans results in at least one rim—a narrow ring slightly larger than the outside diameter of the rest of the can. The flat surfaces of rimmed cans are recessed from the edge of any rim (toward the middle of the can) by about the width of the rim; the inside diameter of a rim, adjacent to this recessed surface, is slightly smaller than the inside diameter of the rest of the can.

Three-piece can construction results in top and bottom rims. In two-piece construction, one piece is a flat top and the other a deep-drawn cup-shaped piece that combines the (at least roughly) cylindrical wall and the round base. Transition between wall and base is usually gradual. Such cans have a single rim at the top. Some cans have a separate cover that slides onto the top or is hinged.

Two piece steel cans can be made by "drawing" to form the bottom and sides and adding an "end" at the top: these do not have side seams. Cans can be fabricated with separate slip-on, or friction fit covers and with covers attached by hinges. Various easy opening methods are available.[4]

In the mid-20th century, a few milk products were packaged in nearly rimless cans, reflecting different construction; in this case, one flat surface had a hole (for filling the nearly complete can) that was sealed after filling with a quickly solidifying drop of molten solder. Concern arose that the milk contained unsafe levels of lead leached from this solder plug.