ONCE AGAIN THE DESIRE FOR EXPANSION AND WEALTH, and the necessities of war, broadened the popularity of the can. Manifest Destiny and the California Gold Rush of 1849 sent miners, homesteaders and trappers into the frontier. A considerable amount of provisions was needed to make the long journey across the plains and the mountainous West. Settlers traveled in wagon trains filled with supplies and herded livestock alongside their caravans. Foods canned in the East were critical for survival.

Roly Poly tobacco tins, manufactured by the Tin Decorating Co. (Tindeco) of Baltimore, MD, c. 1912. From left to right, "Mammy," "Satisfied Customer," and "Singing Waiter."

Still, tragedy and starvation were common. It was the gruesome fate of the Donner party in 1846, an 87-member group reduced to cannibalism when deep snow trapped them in the Sierra Nevada mountains, that set one determined inventor to work on a canned food innovation. Gail Borden was inspired by the need of travelers for nutritious food that took up little space. He first tried a meat biscuit—condensed meat and vegetables—which was a culinary and financial disaster. Borden became an overnight success however when he hit upon canning condensed milk.

An early version of th eaerosol can

Borden was not the first to can milk, but he soon became the best. Not only was Borden's Eagle Brand the most palatable, it was the most promoted. In 1856, he set up a cannery in Connecticut and began to target the New York City market. In those early days of urbanization, the milk that reached the city was often of poor quality. Cows at dairies on the outskirts of the city were fed waste from liquor distilleries and other dubious sources. The milk often required adulteration to make it look more like milk. What's more, it was sold in bulk in open barrels in crowded, dirty stores and transported to market in uncovered containers on the back of a horse-drawn wagon amid the filth and dust of city streets. Borden advertised his product as cleaner, purer and fresher than anything else New York residents could buy.

Besides creating a brand name that we still trust today, his marketing savvy had other important consequences. His condensed milk business essentially changed the way dairy farmers operated. It expanded and facilitated their market reach into areas far away from the farm, as well as greatly increased demand. And the appeal of purchasing clean, fresh products protected by sturdy tinplate was not lost on other food producers. Whereas staples such as flour, tea, and crackers were traditionally purchased from large barrels in general stores, vulnerable to insects, pests and moisture, these products quickly became available in individual servings in containers of tin and other materials. Soon everything came in tins: chewing gum, baking soda, maple syrup, talcum power, cosmetics, pharmaceuticals, tooth powder, tobacco, cigarettes and more.

The word "hermetic" comes from the teachings of Hermes Trismegistus, literally "Hermes thrice greatest," Olympian god known as the father of alchemy. It means "made perfectly alright so that no gas or spirit can enter or escape."

Another chapter in American history, the Civil War, also features the can in a prominent role. Soldiers, especially from the North, came to rely on canned rations. In fact, Borden's canned milk is credited with saving many lives during the war. Borden could hardly keep up with the Union army's orders and leased milk processing plants all over the country to meet the demand. When soldiers returned home from battle they were familiar with and trusting of canned products and soon made them a regular part of their household.

In 1861, as the war began, an important discovery was made that would help canneries increase output. It was learned that adding calcium chloride to the water in which the cans were boiled raised the temperature and increased the speed of the canning process. Then the can opener was invented in 1865, making canned products more convenient than ever. And since the war effort competed with can making for metal resources, necessity and creativity introduced thinner cans that remained sturdy while using less tin. Annual production of canned foods increased six-fold—from five million to 30 million—by the end of the Civil War.