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OUR OIL FLASKS* 



Oils ? Of course every one knows what oil is. Florence oil — for salads 

 — comes from Florence in those thin flasks always on one side, with a 

 wicker covering that never stands straight, stoppered with cotton wool, 

 or the blunt end of the little straw tassel, when people are untidy 

 and put things to wrong uses ; — comes out of the olive berry, those 

 mouldy-looking green things, all salt and oil, which one eats after 

 dinner and thinks very nasty, but daren't say so, and doesn't know what 

 to do with the stones, when one is young and shy and not up to all the 

 niceness of table-manners. Surely there is nothing so very particular 

 about oil that one need make an article out of it ! And yet it has some 

 curious facts and circumstances connected with it in its various appear- 

 ances ; quite curious enough for a ten minutes' rapid reading among 

 the graver tasks of the day. 



There are two kinds of oils, the fixed or fatty, and the volatile or 

 essential. The first are bland and mild to the taste, and, whether of 

 animal or vegetable origin, are all composed of oxygen, hydrogen, and 

 carbon, but with a large proportion of carbon, which makes them good 

 for food and light. They are the chemists' " oils," " tallows," and 

 " butters." The second are hot and pungent, chiefly used in perfumerj r 

 and as stimulants in medicine, and of a very varied chemical composi- 

 tion — some containing only carbon and hydrogen, as the oil of turpen- 

 tine ; others adding oxygen, as the oil of cloves ; and others containing 

 sulphur, as the oil of garlic. But our present flasks are all filled with the 

 fixed or fatty oils : the volatile or essential must wait their turn. 



By the discoveries of Chevreul, " the father of the fatty acids," as he 

 is called, the fixed oils are known now to have three invariable con- 

 stituents, oleine, margarine, and stearine — all compounds of glycerine 

 with fatty acid — and it is according to the greater or less proportion of 

 one or the other that fat is more or less fusible or solid. Thus, oleine 

 is liquid at any ordinary temperature, but margarine is solid up to 116 

 deg. Fahrenheit, and stearine up to 130 deg. Fahrenheit. An experi- 

 ment on these two substances may be made by those fond of chemistry 

 and not afraid of evil smells or dirty fingers. Melt some solid mutton 

 fat in a glass flask, and shake it with several times its weight of ether. 

 When cool the stearine falls in beautiful soft crystals, leaving the mar- 

 garine and oleine in solution. Press out the soft mass of stearine in a 

 cloth, and evaporate the liquid remaining ; you will then get margarine 

 and oleine together, if you press them out through folds of blotting- 

 paper. The residue, dissolved afresh in ether, gives pure margarine ; 



* There are a great many palpable errors in this article, both in botanical 

 classification and in commercial and chemical details ; the writer having evi- 

 dently aimed more at popular information than technological description, but we 

 republish it for what it is worth, although some parts will cause our readers to 

 smile.— Editor, Technologist. 



