64 LITERARY AND SCIENTIFIC. 



producing heat and light, or in other words, of exhibiting the phenomena of com- 

 bustion. The principal distinction which separates these five elements from 

 others, is their electrical relations. Compound bodies, containing any of them in 

 combination with others, when decomposed by the agency of electricity, always 

 present these elements at the positive pole of the galvanic battery — hence they 

 are frequently termed electro-negative bodies. 



The remaining 49 elementary bodies are all opposed in their electrical relations 

 to the first class, and when separated from their combinations, always appear at the 

 negative pole of the battery — hence they are termed electro-positive bodies. 



But these 49 electro-positive bodies are again divided into metallic and non- 

 metallic bodies. The number of the non-metallic bodies is eight — the number of 

 the metals is 41 ; so that by far the greater number of the elementary bodies are 

 metals. 



The eight non-metallic bodies are nitrogen, hydrogen, carbon, sulphur, phos- 

 phorus, boron, selenium, and silicon. These are remarkable not only on account 

 of their electrical relations, but also because they form acids by their union with 

 oxygen, or with some other body of the first class, thus — 



Nitrogen with Oxygen forms Nitric Acid. 



Carbon Carbonic Acid. 



Sulphur Sulphuric Acid. 



Phosphorus Phosphoric Acid. 



Boron Boracic Acid. 



Selenium Selenic Acid. 



Silicon Silicic Acid, or Silica. 



Hydrogen does not form any acid with oxygen, but with chlorine it constitutes 

 muriatic acid. 



Of the 41 metals, some of them were known at an early period of time, while 

 others are of very modern discovery. Tubal Cain, we learn in the 4th chapter of 

 Genesis, was an artificer in copper and iron, and it is probable this person is the 

 same that is spoken of in fabulous history under the name of Vulcan. 



The following table contains a list of the metals, and the dates of their discovery : 



Gc^d^Silver. Iron, Copper.Mercury. L^^^^^^^^ 



Antimony described by Basil Valentine 15th Cent. 



Zinc /■• •• Agricola 1520 



Bismuth Paracelsus l6th Cent. 



Arsenic and Cobalt Brandt 1733 



Platina discovered by Wood, Assay Master, -i .^.. 



Jamaica j ^ 



Nickel Cronstedt 1751 



Manganese Gahn and Scheele .... 1774 



Tungsten M, M. D'elhuyart 178J 



Tellurium MUller 1782 



Molybdenum • Hielm 1782 



Uranium Klaproth 1789 



Titanium Gregor 1791 



Chromium Vauquelin 1797 



Columbium Hatchett 1802 



Palladium and Rhodium Woolaston 1803 



Iridium and Osmium Smithson Tennant . . , . 1803 



Cerium Hisinger and Berzelius 1804 



Potassium, Sodium, Barium, Strontium, \ «,> h now lonT 



Calcium / hirH.uavy I807 



Cadmium Stromeyer 1818 



Lithium Arfwedson 1818 



Zirconium Berzelius 1824 



Aluminum, Glucinum, Yttrium Wohler 1828 



Thorinum Berzelius I829 



Magnesium Bussy 1829 



Vanadium Sefstrom 1830 



The characteristic properties of metals are the following : — They are good con- 

 ductors of electricity and of caloric. They are perfectly opaque even when reduced 

 into thin leaves, and when polished they are good reflectors of light, and possess 

 considerable lustre. When the compounds which they form with the elements of 

 the other classes are submitted to the action of galvanism, the metals always 

 appear at the negative end of the battery. 



