Treatise on general and industrial inorganic chemistry / by Etore Molinari ; third revised and amplified Italian edition translated by Ernest Feilman.
- Ettore Molinari
- Date:
- 1912
Licence: In copyright
Credit: Treatise on general and industrial inorganic chemistry / by Etore Molinari ; third revised and amplified Italian edition translated by Ernest Feilman. Source: Wellcome Collection.
31/734
![plienomena are based on contimioua Chemical transformations, and these are always founded on thè ahaolute indestriictibility of matter. In all tho imnìcnso universo, in thè infinite transfonnations vliich matter eontinnally undergoes, not a single jmiicle is lost, and a few grammes of matter will exist nnehanged in thè universe a million yen,rH later, and will weigh exactlv as miich to-day as they have weighed for a million yearsd HISTORY OF CHEMISTRY Now thafc we have songlit to explain by rational hypotheses the essence of Nature in her various forms and transfonnations, wc will glauco at past ages in order to gradually follow the investigations of oiir predecessors on this important qiiestion. We will thus have an idea of the dovelopment of human thought in the interpretation of nature and of the Principal plienomena which atfect the human senses, in order to then give an explanation of thè manner in which the rational conceptions of modern Chemical Science arose. THE EARLIEST CIVILISATION. We will turn backwardsin the story of mankind, back to the commencement of historie documents and positive descriptions, and stop when the ancient legends no longer permit true history to become apparent. We will go beyond thè Middle Ages, the Roman epodi, that of ancient Greeee, 500 years b.c., and further back stili to the first Egyptian civilisation. . . . But even then we must in fairness and justice pass beyond this to the ancient Chinese civilisation and the Assjtìo- Babylonian civilisation, to a civilisation which is irrefutably recordcd, and which would have bceii stili greater if, for their warlike and religious undertakings, the rulers had thought flt to demand conscientious and honest scientists. Whilst in the rest of the world barbarism was stili supreme, in China, 3000 years b.c. and in AssjTia and Babylonia 5000 years b.c., there was already a eivilisation mudi superior to that of the other nations who were stili groping in thè primitive chaos of the rudinientary formation of human organisations. Agriculture flourished, and industry, which even many centuries later was in its infancy in other continents, had risen to important devdopment in these parts of Asia. We stand astonished before the art of our greatest artists, before the pictures of the period of Giotto and the Byzantine epodi ; but what shall we say of the truly admirable Works of art which the yellow man produced 2000 and 3000 years previously ? When we admire the very beautiful works of Michelangelo, who reprodueed nature so ably and studied plastic anatoniy by dissectiiig parts of animals and plants in order to study tlieni more dosely, what shall we say of tho surprising roproductions in pictures, sculptures, and carvings made by Chinese about 2000 years previously and by the niost ancient Egyptians 4000 years before ? Faithful and marve]lously exact reproductions of naturo alivo and dead on linen, bronzo, in copper, stono, and silk, and with sudi harmonious and simple artistic feeling that they are capable of inspiring the artists of to-day ! Already 1000 years b.c. the walls of thè Chinese palaces were paintod and decorated ; and 200 years b c. the art of portrait painting flourished. Whilst tho powerful Ronians in their frenzied luxury, which led to corruption of their inorais and total decadence, used ridi silken fabrics imported from Asia, in China the ‘ Tho lawof tho conscrvation of mass has not found any cxceptions, ami all tho oxact scicnoos accopt as an iincliscussod axiomtho rosults of a ccnturyof varied resoarchos and inmimerahlo oxporimcnts. AH the sainc, tho cxpcrimcntal control of a law of sudi importancc is always intcrcsting, just as niiich so to-day, whon scicnce has at its disposai sudi pcrfcct and rigorous apparatus, as in tiinos past, from Lavoisier until now. Landolt and Hoy- dweillcrtook up this question (1893, 1900, 190.5) with tho most oxact oxporimcnts requiring a largo amount of Work. In two arms of a U-tubc they placcd two mutually roactivc substances ; tho tube was then scalod in tho blowpipc and the wholc weighed on a most oxact balancc (weighing to 0’03 mgrm.) ; aftor agitating and mixing the two substances, and wlion the Chemical roaction was completed, tho wholc apparatus was roweighod. Of soventy-five rcactions, produced with hundreds of grammes of matorials, sixty-onc showod a vory slight diminu- tion of woight, which in the case of silver suliihato and forrous sulphato roso to 0'3 mgms. jicr 100 gnns. of silvor. It has boon argued from these faets that in tho shock of thè atoms producing tho new chomical roaction niinimal tracos aro split off from these atoms (they appoar not to bo oloctrons—see Electrons helmv) and are disporsod by passing through the walls of tho glass vessel. As a matter of fact, on coatiiig thè walls of tho roaction chamber with parattin tho diminution of weight disappoared, even in thè case of ferrous and silvor suli)hatos. In tho last sories of experiments carriod out by Landolt until 1908 tho small dilfcronces previously observod are explained ; the small diminutions in woight aro also obtaincd before thè roaction if tlic substances are hoated up to the tem- perature of reaction before they are mixed.](https://iiif.wellcomecollection.org/image/b28134187_0033.jp2/full/800%2C/0/default.jpg)
