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Natural History of Cold.
51 the uncoothness of the language, the Natural History of Cold. soggedress of the Atyle, or the disproportion aod extravagance of the ima
(Continued from Page 27.) ges. Speakiog of the pins he says,
rome (ubftances it melts failer than lood resound,
upon others, nor can we assigo any And jarriog difcords iend th'afto cause for the difference ; it melts nith'd ground.
sooner in a silver plate thao upon the 80 #beo aloli dire hurricanes arise, palm of the hand; and it melts sooner And with horrendous fhatterings upon copper than any other metal barft the tkies,
whatsoever. Ice melts sooner in waDread ghaftly terrore drive along in ter than exposed to the air of a fimilar crowds,
temperature, sooner in water a little And hideous thunder howls amongft warm than near the fire where it is the clouds ;
horter. It melts sooner in the void Eternal whirlwinds on the ocean
than exposed to the atmosphere. If it roar,
takes twenty minotes to diffolve in lognite earthquakes rock the open air, it will be but four minutes bounding More."
diffolving in the exhausted receiver. 1 fhall conclude there remarks upon · It takes a much longer time to melt bombafl, with ag observation which than it does to form. Water congealI ought in justice to make, in favour ed in fix minutes, takes some hours to of those who fall into it; viz That resume its fluidity, if placed in such 20 person can be a considerable profi. air as would not freeze it naturally, Ceat this way, who has not a good and yet of moderate coolness. Upon fare of natural powers and abilities. this principle it is that ice houses are Hence, when we see a young man de- formed, for we must not imagine that, livering homself in this warm mander, at the ordinary depth to which these he is to be regarded as a good genius are sunk, water would congeal if left run wild, for want of cultivation from to itself. On the contrary, water ftudy, and the rules of art : And it brought there always preserves its follows, that fould such a juvenile Auidity. The large masses of ice or writer, take proper methods to im. snow that are placed there, melt in prove his m od, by innuring himsell some proportion ; but as their thaw to a close way of reasoning, and by is carried on very flowly, there is ftill converfing, with the best authors, sufficient quantities of ice left for the however defective he might be in purposes of luxury. this particular at first, he would in the of all Auids oil of olives freezes ead make a challe and excellent wri- foones, and other oils in succession ; ter. Thus it happened to the immor. - I mean of those oils that have beea tal Virgil, whole divine Eneid once made by pressure, not by diftillation. Mot itself into to great a luxuriance, Water and such insipid liquors follow as to be dear twenty times as 'large as next, then spirits of wine, and all it appears at this day. As his imagi- . fp rituous liquors, which however take Dation cooled by years, and his jodg a large quantity of freezing cold to meat tipeaed, and hafted on to maru. congeal them. The mof waterý rity, his ftyle dropped the false glare parts of these begin to freeze first, of ordineats, and thone with an equal while the stronger fiery spirit flies to purity and elegance ; his thoughts the centre, and frequently is found learned to proportion themselves to concentred in the midst of che calk in tus subjea, and call themselves into the hardest frosts, ftill preserving its that ezaa symmetry of arrangement Auidity. Spirit of nitre and such acid and disp»firron, in which they now fpirits, as well as vinegar itselégreatly charm os ; and, in a word, a new beau. regit congelation, tho' they are found ty began to dawo in every line of not able to endure extreme cold, that exquifiie wosk which consecrates which at length deftroys their Auidibis deathless fame to the admiration of ty. Quick-silver, it was thought till all pofterity.
of late, was not to be congealed by any degree of cold whatsoever. Bu
in this naturalists were mistaken ; for stances grow colder by the fluids they the royal academy at Petersburg, contain or are mixed with being evahave not long since congealed it into an porated. If both these mernods, icy mass by a method well known to therefore, are praétised upon the same almoft every philofopher before, but body at the same time, they will in profecuted by none of them with equal crease the cold to almost any degree of perseverance. The Ruffian acade, intenreness we defire. mifts only used the same arts by The Russian experiment at Peter. which philosophers were accustomed Iburg, or congeaing quick filver was to make artificial ice at pleasure. We thus : At a time when the quick-filfhall firit give the common method of ver was found to have fallen extrememaking ice, and then the new art of ly low, and the cold consequently to freezing quick filver,
be very intense, the mercury being by It was said in the beginning of this de Lille's thermometer, which is beft chapter, that fal ammoniac being adapted for measuring the degrees of mixed with pounded ice or snow, cold, as Fahrenheit's for measuring melted them, and at the same time those of heat, being, I say, by this made them co!der. A similar, tho' thermometer, fallen to 250 degrees, not so intense a cold, may also be thus they encreased the cold by mixing the given to snow-water by aliy salt what. fuming spirit of nitre, and having lover ; such as alum, copperas, fali- been left to cool in snow, with half as petre, or common sea fult, which we much snow in a common glass, stirr. vse at our tables. Now, if we take ing it till it becomes of the confiftesce about four pounds of snow, or pound of pap, the thermometer being dipped ed ice, and mix them with about a pound of falt; in this composition, if funk to 470 degrees. Upon a repeti
into this composition, the quick-silver we set a water glass upto the edges in tion of this experiment, when the water, and filled with water, we shall foon ieethefalt diffolve the ice or (now; ner of water, inflead of diiating fill
mercury (which contrary to the man. but while dissolving, it will at the same continued to contra&t with increased time freeze the water in the glass into cold) funk to 500 degrees, they broke one solid mass of ice, or at least will the glass, and it was found frozen into Jeave a fufficient quantity flicking to an hard folid mars ; but what was the fides to thew the truth of the most extraordinary, 'it bore the ham. experiment.
mer like a common metal, and was Naruralifts all in filt upon the ne- beat into the shape of an half crown, ceffity of using falt of some kind or Aulaft however, it began to break,and other in th sexperiment ; but I have being thawed, recovered its former often made ice by the fire side, with. fluidity. From hence we see that the out any falt whatsoever, and which spirits either of salt or nitre, are posevery person that pleales may readily fessed of the power of cooling liquors try. It is only to hll a small deep in a much higher degree than the pewier dit with water and upon that common substances in concrete. to place a common pewier plate filled, common salt.petre fiks the thermo but not heaped with snow. Bring meter to a degrees, spirit of nitre this simple apparatus near the fire, itir will be found to fink it eight degrees the inow in the plate with a cane or ftill lower, as has been discovered by any other instrument. The snow will Fahrenheit. From all that has been diffolve, and the ice will be formed said upon this subject, we can give upon the back of the plate which was probable reasons for the different desee in the dish of wa'er. I have tried grees of cold in different regions it frequently without salt, and it an- though under the same latitude, and (wers. though not with equal efficacy. confequently blefled with equal proBut of late there has been a more portions of rolar beat. Thus for ineffectual method of congealing fluids Rance, the latitude of Moscow and than any yet mentioned. It has been Edinburgh, is precisely the same, yet discovered that Auids fland og in a in the one the cold is often found to current of air, grow by this means be forty degrees greater than freezing much colder than before. It has while the other seldom feels above been discovered also, that all sub. five. One reason may be that the air
Elay on Tafie. .
T.e regions of North- dramatic compofition!
Wiat conclusion are we to forn
ard of life, by appealing to which we
bad taite? Or is there in truth no
such diftin&ion; and are we to hold
according to the proverb, chere is no
If ihere be no such thing as any come next to consider its deviations
Atandard of tafte, this consequence
muft immediately follow that all caftes
are equally good ; a position, the abr
will serioully maiotain that the taste of the toft difñcult part of our task. For
a Horrentot' or Laplander is as deliit muft be acknowledged, that no prin.
cate and correa as that of a Looginus ciple of the human mind is, in its oper
or an Addison? or that he can be
who thinks a common news writer as
excellent an hiftorian as Tacitus ?
the preference of one man's taste to
that of another ; or, there is a good
as in other things.
The diverfity of taftes which pre-
vails among mankind, does not in
The tastes of men may differ very
relishes poetry moft ; another takes
are amused with gay and
are more entertained with those of a
graver call. It is not in matters of
where there is but one conclusion that vails in Great Britain now, from what
can be true, and all the rest are erro. prevailed there no longer ago than the
Qeous. Truth, which is the obje&t of