Familiar letters on chemistry, and its relation to commerce, physiology, and agriculture / by Justus Liebig ... ; edited by John Gardner.

  • Liebig, Justus, Freiherr von, 1803-1873.
Date:
1843
Catalogue details

Licence: Public Domain Mark

Credit: Familiar letters on chemistry, and its relation to commerce, physiology, and agriculture / by Justus Liebig ... ; edited by John Gardner. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    taining condensed oxygen. When a jet of hydrogen gas, for instance, is thrown upon spongy platinum, it com- bines with the oxygen condensed in the interior of the mass ; at their point of contact water is formed, and as the im- mediate consequence heat is evolved; the platinum becomes red-hot and the gas is inflamed. If we interrupt the current of the gas, the pores of the platinum become instantaneously filled again with oxygen; and the same phe- nomena can be repeated a second time, and so on interminably. In finely pulverized platinum, and even in spongy platinum, we therefore possess a perpetuum mobile—a mechan- ism like a watch, which runs out and winds itself up—a force which is never exhausted—competent to produce ef- fects of the most powerful kind, and self-renewed ad infinitum. Many phenomena, formerly inexpli- cable, are satisfactorily explained by these recently discovered properties of porous bodies. The metamorphosis of alcohol into acetic acid, by the process known as the quick vinegar manufac- ture, depends upon principles, at a knowledge of which we have arrived by a careful study of these properties. LETTER III. My dear sir: The manufacture of soda from common culinary salt may be regarded as the foundation of all our modern improvements in the domestic arts; and we may take it as affording an excellent illustration of the depend- ence of the various branches of human industry and commerce upon each other, and their relation to chemistry. Soda has been used from time imme- morial in the manufacture of soap and glass, two chemical productions, which employ and keep in circulation an im- mense amount of capital. The quantity of soap consumed by a nation would be no inaccurate measure whereby to esti- mate its wealth and civilization. Of two countries with an equal amount of popu- lation, the wealthiest and most highly civilized will consume the greatest weight of soap. This consumption does not subserve sensual gratification, nor depend upon fashion, but upon the feeling of the beauty, comfort, and wel- fare attendant upon cleanliness; and a regard to this feeling is coincident with wealth and civilization. The rich in the middle ages concealed a want of cleanliness in their clothes and persons under a profusion of costly scents and essences, while they were more luxu- rious in eating and drinking, in apparel and horses. With us a want of clean- liness is equivalent to insupportable misery and misfortune. Soap belongs to those manufactured products, the money value of which continually disappears from circulation, and requires to be continually renewed. It is one of the few substances which are entirely consumed by use, leaving no product of any worth. Broken glass and bottles are by no means absolutely worthless; for rags we may purchase new cloth, but soap-water has no value whatever. It would be interesting to know accurately the amount of capital involved in the manufacture of soap ; it is certainly as large as that employed in the coffee trade, with this important difference as respects Germany, that it is entirely derived from our own soil. France formerly imported soda from Spain, Spanish soda being of the best quality, at an annual expenditure of twenty to thirty millions of francs. During the war with England, the price of soda, and consequently of soap and glass, rose continually; and all manufac- tures suffered in consequence. The present method of making soda from common salt was discovered by Le Blanc at the end of the last century. It was a rich boon for France, and became of the highest importance during the war of Napoleon. In a very short time it was manufactured to an extraor- dinary extent, especially at the seat of the soap manufactories. Marseilles pos- sessed for a time a monopoly of soda and soap. The policy of Napoleon deprived that city of the advantages derived from this great source of com- merce, and thus excited the hostility of the population to his dynasty, which became favourable to the restoration of the Bourbons. A curious result of an improvement in a chemical manufac- ture! It was not long, however, in reaching England. I o o In order to prepare the soda of com- | merce (which is the carbonate) from