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Show 96 SAL'f·l\IAKINO. moment dividing the waters of every navigable stream, and the waves in every ocean, in and between all highly-civilized and active countries ; and if, when one is in St. Paul's, "look around" be enough of reminiscence for the genius of Sir Christopher Wren,-climb the highest mountain, get the mo8t ample range of land and sea; and, in what part soever of the busy world it may be, " r.ooK AROUND" will still be the epitaph of James Watt. But what he and his co-operatives have don~ is hnt a single series of the applications of that one property of water. Those applications are very many, and our salt-making is one and a highly important one; and there are places where, if the people could find materials, they would prize the making of salt more than the making of gold. It is reported that there are some tribes in Africa who give away I gold-dust, but reckon value in salt as we do in monry. Well, the moment that the water is raised to the boiliug point, it will receive no more heat into its substance, or allow any more to pass through without exerting the resistance to which allusion has been made; and if it is not everywhere resisted in return by something stronger than its own resistance, a portion of the water goes off, and carries the heat along with it, so that the water where it just begins to mingle with the air is far hotter than it is at the bottom of the vessel. Every one has noticed the force with which the steam of water in a teakettle issues from the spout, and may have seen the force of boiling water drive off the cover of a saucepan; and it is said, and possibly it is true, that the di8covery of the steam-engine was owing to one or other of these ; but when, as in boiling brine for salt, the surface of the water is freely exposed to the air, the heat and water go off together; and if the boiling were continued long epough, the water would pass entirely into the atmosphere. Salt does not pass so easily into vapour as water ; and, there- 5UCCESSION AND CHANGE 97 tore, as the water boils off . . ~iquid becomes salter and ~~l~e~P~U:tilt:~ Iemt atthning Is much more salt th tl ' . . as ere keel? dissolved if it w~~e ~~l~~m~}n;~g bw~1t_er could earned on too 1 h e Ol mg were matters in the ~~[{;rt !~~J~' ~og~t~er ;vith the other ihe bottom; but the ~alt-m e~m 0 "orm a crust at proper strenoth to which tt~e~s.hereh observed" the and they st;p the boilino- ~ J1 ~1 f1 s ould be boiled; cool, in that state when o n . a ow the water to ~sis sufficient to overco~~ere IS ~ot so muc~ water mvisible atoms of salt ha ihe~ tendency whiCh the crystals, and so as the s~~ 0 orm thems_elve~ into acts in nature, the salt cr of~r.r power mva~tably thus obtained by motion (~ts b..-l tzes. T~e bnne is ii1rr · d" f 1 ecomes brme by th o.l e tents o water and salt h. h e fom: in number, movino- in ':v JC a~e ~t the least nexwn with each other) ~h a ~e.ry ~nhmate con-t mhotion; th.e surplus wat~r is c~rrf~~eo~ ~arme~ by e water 1s cooled b m t. .Y motwn; heat out of it), and the~alt~ 1011 (thf. motwn of the If we were to follow th s crysta hzed by motion. the salt, or any other s~tifrocesses through which even in the longest series os;a~ce whatever, passes should invariabiy find each ~ anges or events, we of some kind or other. c ange to be a motion motion always arose fr~rnand that any particular {beyond which we co-uld ~o~e ?ower or sat~rce overcoming another ow o . trace t~e motwn) stronger would h p er whtch, had It been the result; ~nd given ~~~ raro~~~ed ~·totally dilf~rent appearances Take ~ . q t e a liferent cham of and steep ii in wate~ o; ms_ an~e, a ~ushel of barley, the water, and swell a~d nbd It W1ll drmk up some of ~md begin to sprout ; and efom_e sugary to the taste, lS steeped by the maltster t Will do. that whether it steeped by the moisture r' t~r tsown tn the earth and of events is begun wh. ~ . a · Thus, a succession no farther than th~ gr~fn fI ~ ~ac1h case we can traco ar ey, unless we trace |