1024 FOODS AND FOOD ADULTERANTS. 



save as a carrier of living organisms. Boiled infusions of a great many 

 of the common food materials were subjected by him to the action of 

 air from which solid matter either had been removed or had been ren- 

 dered inert by heat, and these decoctions did not decay, but remained 

 unchanged for long periods. In this connection he demonstrated the 

 fact that air passed through loosely packed cotton or through a red-hot 

 tube permanently lost its power of infection. 



Based on the erroneous idea of the necessity of oxygen to the decom- 

 position of organic materials, many processes were proposed in the first 

 half of the century for the preservation of food by exclusion of air. In 

 1810 Augustus de Heine proposed to exhaust the vessel contain ing food 

 by means of an air pump, but the process did not answer. In 1828 

 Donald Currie proposed an improvement, which consisted in allowing 

 carbonic acid gas to enter after the extraction of the air. Later, Leig- 

 nette (1836), Bevan (1842), Eettie (1846), and Ryan (1846) proposed 

 other improvements, but none of these were successful. 1 Jones and 

 Trevithick devised an improvement which consisted in admitting pure 

 nitrogen after exhausting the air, once more exhausting, and finally ad- 

 mitting a mixture of nitrogen and sulphurous acid. This process was 

 quite successful, but the preservation of the food was quite evidently 

 due to the antiseptic action of the sulphurous acid and not to the exclu- 

 sion of air. At present this method has merely a historical interest. 



Since the days of Saddiugton and Appert, preservation of food by 

 their process has become one of the world's great industries. Canner- 

 ies dot every country of the earth and their product is found on every 

 table. All manner of food is canned, and that at prices which place it 

 within the reach of the humblest pockets. Preserved food has been a 

 great democratic factor, and has nearly obliterated one of the old lines 

 of demarcation between the poor and the wealthy. Vegetables out of 

 season are no longer a luxury of the rich. The logger may to-day have 

 a greater variety of food than could Queen Elizabeth have enjoyed 

 with all the resources and wealth of England at her command. In the 

 American grocery pineapples from Singapore, salmon from British 

 Columbia, fruit from California, peas from France, okra from Louisiana, 

 sweet corn from New York, string beans from Scotland, mutton from 

 Australia, sardines from Italy, stand side by side on the shelves. 



In the United States the canning trade has kept full pace with the 

 wonderful development of the country. Its extent may be judged by 

 taking the statistics for one single product green corn. In 1892 the 

 pack reached the enormous total of 84,700,000 cans. 2 



Yet great as is this industry it has attracted little attention from 

 those charged to guard the welfare of the people against either the 

 skill or the carelessness of the food adulterator. Abroad a little scat- 



1 Letheby,-Chem. News (Amer. Repr.), 1869, 4, 74. 

 American Grocer. 



