Show the magic fagi of chemistry j chemists Che chemistry yhone is one of the most attractive sciences from the beginning to the eydthe end the i student is sup surprised rifled ana and delighted with the developments 0 of the exact discrimination I 1 as welt well as the power and capacity which are displayed in varl various lons forms of chemical action dissolve two substances in the same fluid and then by evaporation or otherwise cause bause them to assume reassume re a solid form and 11 4 each particle will unite with its own kind 1 to the entire exclusion of all others thus I 1 stil sulphate phate of copper and carbonate cor bonate of soda 1 are hare dissolved in boiling water and then the water is evaporated flach each salt aalt will be re for foi I 1 ii mod med as before ahito phenomenon fieno menon is the I 1 result of one of the first principles of the 1 1 science and massuch as such is passed over without thought but it is q a wonderful phenomenon and made of no account 0 only I 1 by the fact I 1 that it is id so common and so na familiar I 1 it is by the action oi or this sarae same principle cc elective affinity by which we produce the curious experiments with sympathetic inks by means of these we may carry on olf a corm which i is beyond the disc discovery advery of baj all not in the seer secret t with one class of these inks the writing becomes visible only when moistened with a particular solution thus if we write to you with a solution absolution of sulphate of iron the letters are invisible M on the receipt of our letter lette i r you rub over I 1 the sheet a feather or sponge onge 1 wet with solution of nut galls and th the e letters burst forth I 1 i into sensible being at once and are perma nent 2 if we write with a solution of sugar of lead and you moisten with a sponge or pen cil dipped in water impregnated with sul phu rated Sy hydrogen drogen the letters will appear 1 with brilliancy I 1 3 if we write with a weak solution of sulphate of copper and you apply ammonia the letters assume a beautiful blue when 1 the ammonia evaporates as it does on exposure to the sun or fire the writing disappears pears but may be revived again as before 4 if you write with oil of vitriol very much df diluted so as to prevent its destroying the paper the tha manuscript will be invisible except when held to the fire when the letters win will a appear ear black I 1 5 71 write ite with cobalt dissolved in diluted t 0 acid the letters will be invisible when cold but when warmed they will appear a bluish green I 1 we are almost sure that our secrets thus wr written will not be brought aught to the knowledge of a stranger because he does not know know the solution which was used in writing P and therefore knows not what to apply to b ring bring out the letters 0 other ther forms of elective affinity pr produce duce equally novel results thus two invisible ga gases T when combined form some times a visible V solid Maria tic acid and ammon ammonia la are examples also amm ammonia onia and carbonic acid on the other hand if a solution ot of sulphate of soda be mixed with a solution of of lime the whole becomes solid some gases when united form liquids liquid sI as oxygen and hydrogen which unite and form water some solids when combined form liquids nitrate of ammonia and sulphate of soda when rubbed together in equal proportions in ina a mortar become fluid acetate of lead and sulphate of zinc in equal proportions rubbed in a 4 mortar produce a fluid alaid and so will acetate of lead and glauber salts the union gofoth of other I 1 substances produces a 4 wonderful change of temperature sulphuric acid poured into water will so increase the temperature as to make it uncomfortable to hol hold the vessel containing it if one part of ice is dropped t I 1 into four parts of sulphuric acid cool cooled to the freezing point 32 deg the mass will suddenly rise to fo the boiling point certain other mixtures produce as an intense cold and are called freezing mixtures among these are the following to 32 drams adrams of water and 11 of of ammonia 10 of nitrate of potash and 16 of sulphate of soda all finely powdered and immerse your thermometer and note the result if equal weights of of lime finely powdered and fresh fallen snow are mixed a similar result is produced 13 lbs of each have frozen 56 lbs ibs of quicksilver into a solid mass sometimes a change I 1 of color is produced by similar means thus dissolve copper copp er in sulphuric acid the solution is blue dilute dilate one part of nitric acid with five or six parts of water and throw in some copper fil filings 11 a after a few moments if you pour off tz te e i colorless fluid and add a little liquid ammonia the mass will become blue by similar processes odorous substances become mo inodorous dorous and the reverse and other changes equally remarkable are as f familiar am to the chemist as the alphabet of his native tongue buethe most astonishing exhibitions are witnessed we thinly ic combustion A great variety of experiments come under this title presenting very dissimilar appearances the comparatively comparative ty alow process proa of fermentation by which the in interior a bior OP of your compost heap is made hot is one fo form im of combustion so iq io the glow worm foght of phosphorous exposed to the ry temperature of the atmosphere other exhibitions in this department present an almost infinite variety of form and condition from the dim light bat powerful heat of burning hydrogen or alcohol to the insufferable light and heat of burning iron iron under the compound blowpipe blow pipe from the bright light but scarcely I 1 perceptible heat i of phosphoric oil with which boys sometimes light up their own hands and faces to the powerful action of that same substance phosphorous when immersed in oxygen gas we have a series of developments as ag various various in in appearance as they are wonderful all these phenomena differ only in their conditions and not in their essential characteristics can you really believe that the neat heat 5 we use the word in its popular sense by which IL your house is warmed is actually in the coal or the wood while it is piled up lip I 1 in n your cellar or your outhouse out house bouse yet so it is were its latent heat balled into a sep sensible sible state where it lies your buildings would catch the infection ec and all consume together 0 why does not the fuel burn barn in the woodpile as it does on the hearth something sets it on fire what is that something Is anything a added de d to the wood not in contact with i it t before whence comes the heat of the mixture of sulphuric acid and ice before named Is that set on fire by some other burning i body now how does phosphorous get on fire when left exposed on your table these processes aye are all alike wonderful wondern al the phenomena exhibited by setting free this latent entreat heat the heat not cognizable by the senses not even by the nicest instruments at t a previous moment are utterly astonishing throw a little of into a vessel of water and it takes fire on the surface throw a little potassium into water and it burns barns rapidly under water water sets it on fire all alia lo la tant bt libat whuell bow par vades the substance of th the e earth sud suddenly enly made free as it might I 1 be by mere action without the application of any foreign ei agn burning body the whole globe w with ishall all it its mountains ins of rocks its iron and metals and its mighty seas would be con fumed we do not undertake to explain the phenomena we have described but only suggest them as incentives to the lovers of the marvelous to examine the subject in a systematic manner the merely curious mind will find more to feed upon in this department of natural wonders than in all the fictitious stories which ther the press has ever issued truth is more wonderful than fiction selected |