C|)e popular detente i^etus 



AND 



BOSTON JOURNAL OF CHEMISTRY. 



Volume XXIII. 



BOSTON, MARCH, 1889. 



Number 3. 



CONTENTS. 



Familiar Science. — Simple Chemical Experi- 

 ments 33 



The Jardin des Plantes 33 



Experts 34 



A New Primary Battery 35 



Coloration of a Coal Fire by Common Salt . 36 



Some Old Trees 36 



Apparatus for Studying Insects Under Ground 36 



The Telautograph 36 



Detection of Antimony in Minerals ... 36 



Scientific Brevities 36 



Practical Chemistry and the Arts. — An 



Immense Dynamo 37 



Photographs of Electric Sparks 37 



Laboratory Notes 37 



The Constituents of Drinking Water ... 37 



Home, Farm and Garden. — Wine Making . 39 



The Mushroom 39 



On Stewing. Boiling, and Simmering ... 40 



Transmutation of Cotton Seed 40 



To Foretell Frost 40 



Gleanings 40 



Editorial. — Copper 41 



A Simple Pantograph 42 



Notes on Pollens and Fertilization of Flowers 42 



Meteorology for January 43 



Astronomical Phenomena for March ... 43 



A Curious Egg 44 



Q^iestions and Answers 44 



Literary Notes 44 



Medicine and Pharmacy. — Social Organism . 45 



An Extraordinary Beard 45 



Monthly Summary of Medical Progress . . 45 



The Anx'sthetic Revelation 47 



Gum-Chewing. Therpeutically Considered . 47 



Occurrence of Fluorine in the Organism . . 47 



The Consumption of Opium in China . . 48 



Medical Memoranda 48 



Humors .... - 14^ 



Publisher'.s Column 48 



Eaiiilliar Scieijce. 



SIMPLE CHEMICAL EXPERIMENTS. 



The experiments described below, are se- 

 lected for the reason that they can be per- 

 formed with apparatus and materials to be 

 found in in every kitchen or family medicine 

 closet. They illustrate difterent chemical 

 processes and reactions, and are perfectly easy 

 and safe to perform. The more brilliant ex- 

 periments described in elementary text books, 

 require material not always at hand, and are 

 often dangerous when attempted by inexpe- 

 rienced amateurs in chemistry. 



Precipitation. — Dissolve a small bit of 

 alum in plenty of water, and add a few drops 

 of ammonia. An abundant white precipitate 

 will be produced, which will be flocculent or 

 gelatinous, according to the strength of the 

 alum solution. The ammonia has decom- 

 posed the soluble alum, forming alumina 

 which is insoluble in water, and therefore is 

 precipitated out. 



Drop a little cologne or other perfume into 

 a glass of water. A cloudy precipitate will 

 appear which consists of the odoriferous gums, 



resins, and oils, which are soluble in the 

 strong alcohol of the perfumery, but insolu- 

 ble in water, or the diluted alcohol which is 

 formed when they are mixed together. Spir- 

 its of camphor may also be used. 



Slake a small piece of lime, put the re- 

 sulting white powder or paste into a bottle, 

 and pour strong vinegar over it. After a few 

 minutes pour off the clear liquid, and add to 

 it a solution of washing soda, or saleratus. 

 An abundant white precipitate will be thrown 

 down. In this experiment the lime (calcic 

 oxide) by slaking, unites with water, forming 

 calcic hydrate. When mixed with vinegar, 

 which is a dilute acetic acid, a solution of 

 calcic acetate is formed, which, when the car- 

 bonate of soda is added, is changed to calcic 

 carbonate, or chalk, which is insoluble in wa- 

 ter. Separate the precipitate by straining 

 through a piece of blotting paper, and pour 

 some more vinegar over it. The calcic car- 

 bonate will be converted once more into calcic 

 acetate and dissolve, the carbonic acid gas 

 being set free at the same time producing ef- 

 fervescence. 



Effervescence, or the liberation of gas 

 from a liquid may also be produced, bv adding 

 vinegar to a solution of saleratus, by mixing 

 baking powder with water, or by dissolving 

 an ordinary seidlitz powder in water. In all 

 these cases, carbonic dioxide or carbonic acid 

 gas is set free, and causes effervescence by its 

 escape. 



Crystallization. — Dissolve as much 

 alum as possible in boiling water, pour off the 

 clear liquid into a deep dish or bowl, sus- 

 pend a piece of string in it, and allow it 

 to .stand over night. As the solution cools, 

 beautiful crystals of alum will be formed, 

 which, upon examination, will be found to be 

 more or less perfect octahedrons, or eight- 

 sided solids, resembling two four-sided pyra- 

 mids placed base to base. Occasionally the 

 solid angles or points will be truncated or flat- 

 tened, owing to the partial formation of the 

 faces of a cube, as if the alum had attempted 

 to crystallize in the cubic form but only par- 

 tially succeeded. 



Distillation. — Boil some salt and water 

 in a tea-kettle. When the steam issues freely 

 from the spout, hold in it a large bowl filled 

 with cold water or ice. The steam will con- 

 dense into water and trickle down the cold 

 sides of the bowl. Taste some of this con- 



densed water, and note that it has no taste of 

 the salt, from which it has been separated by 

 boiling. 



Congelation. — Mix some snow, or 

 pounded ice and salt together, fill a large 

 bowl with the mixture, and bury in it a 

 small bottle of water. The inixture of salt 

 and snow will absorb so much heat from the 

 water, that in a short time, (about an hour) it 

 will be frozen solid. As water expands in 

 the act of freezing, it is very likely that the 

 bottle will be cracked or broken. 



Efflorescence and Deliqliescence. — 

 If you can obtain some washing soda (sodic 

 carbonate) in crvstals, expose them to the air, 

 and they will gradually crumble into a dry, 

 white powder. This is caused by ths loss of 

 a certain amount of water combined with the 

 tal, and known as water of crystallization. 

 The drying and crumbling process is called ef- 

 florescence. If at the same time yon expose 

 some concentrated lye (potassic carbonate) to 

 the air, it will absorb water from it, become 

 past}' and finally liquid. This process is 

 known as deliquescence. 



Curious Change of Color. — Take a 

 piece of sulphate of copper (blue vitriol) 

 about the size of a pea, which can be obtained 

 of any druggist, and dissolve it in a tumbler 

 of water. The solution will be almost color- 

 less. Then add a few drops of ammonia, 

 (also colorless) and a most magnificent blue 

 color will appear. The ammonia has com- 

 bined chemically with the copper forming a 

 new compound which posesses the character- 

 istic color. 



Fermentation. — Mix some molasses with . 

 about an equal quantity of water ; add a cake 

 of compressed yeast, place it in a large glass 

 jar and let it stand some hours in a warm 

 place. Fermentation will soon commence, 

 and the dextrose and levulo.se of the molasses 

 will be converted into alcohol, and carbonic 

 acid gas, which escapes in bubbles causing a 

 brisk eflervescence. The process can be 

 readily observed through the sides of the jar, 

 and the fermenting liquid is a most interest- 

 ing sight. This process is identical with that 

 which takes place in the " raising" of bread. 



[Original in The Popular Science Neu>s.\ 

 THE JARDIN DES PLANTES. 



BY K. B. CLAYPOLE. 



The Jardin des Plantes, the Botanic Garden of 

 Paris, makes no strong appeal to the aesthetic senti- 

 ments. The elements of beauty are present in 



