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Show [ u6 NoTE v ..... SuN's RAYS. DISPUTE about phlogifl:on; the fun the fountain from whence all phlogi!l:on is de~ rived; its rays not luminous till they arrive at our atmofphere ; light owing to their combufiion with air, whence an unknown acid; the fun is on fire only on its furface; the dark fpots on it are excava_tions through its luminous cruil:. NoTE VI. .... CENTRAL FIREs. SuN's heat much lefs than that from the fire at the earth's centre; fun's heat penetrates but a few feet in fummer; fome mines are warm; warm fprings owing to fubterraneous fire ; fituations of volcanos on high mountains; original nucleus of the earth; deep vallies of the ocean ; difiant perception of earthquakes ; great attraCtion Qf mountains; variation of the compafs ; countenance the exifience of a cavity or fluid lava within the earth. NoTE VJI ..... ELEMENTARY HEAT. COMBINED and fenfible heat; chemical combinations attraCt heat, folutions rejeCt heat; ice cools boiling water fix times as much as cold water cools it; cold produced by evaporation; heat by devaporation ; capacities of bodies in ref peel: to heat, r. Exiftence of the matter of heat {hewn from the mechanieal condenfation and rarefaCtion of air, from the fieam produced in e~haufting a receiver, fnow from rarefied air, cold· from difcharging an air-gun, heat from vibration or fri6l:ion ; 2 Matter of heat analo. gous to the electric fluid in many circumfia-nces, explains many chemical phenomena. NoTE VIII.. ... MEMNON's LYRE. MECHANICAL impulfe of light dubious; a glafs tube laid horizontally-before a firer 1evolves; pnlfe-glafs fufpended on a centre; black .leather contracts in the funfhine ; . Memnon's.ftatue broken by Cambyfes. NoTE IX ..... LuMINous INsEcTs. EIGHTEEN fpecies of glow-worm, their light owing to their refpiration in tranfparent lungs; A<:udia of Surinam gives light enough to read and draw by, ufe of its light to the in feet ; luminous fea-infeCl:s adhere to tha fkin .of thof,e who bath<: in the ports. of.. Languedoc, the light may a rife from putrefcent flimc. NoTE x ..... PHOSPHORUS.. DISCOVERED by Kunkel, Brandt, and. Boyle; produced in refpiration~ and by luminous infects, decayed wood, and calcined !hells; bleaching a flow combuflion in which the water is deeompofed ; rancidity of animal fat owing to the decompofition of water on its furface ; aerated marine acid does not whiten or bleach the hand. It'7 NoTE XI ..... STE.A:M-ENGINE. HERO o.f Alexandria firil: .applied il:eam to machinery, next a French writer in 1 6 30~ the Marqu1s. of Worcc~cr m r655, Capt. Savery in 1689, Newcomen and Cawley added the. p1fl:on ; the Improvements of Watt and Boulton ; power of one of their Ia rg_e engmes equal to two hu nd red horfes. NoTE XII. .... FROST. ExPANSION of water in freezing; injury done by vernal frofis; fifh; eggs, feeds, refiil: congelation; animals do not relift the increafe of heat; frofl:s do not meliorate the gr~und, nor arc in general falubrious; damp air produces cold on the fkin by evaporation ; fiww lcfs pernicious to agriculture than heavy rains for two reafons •. NoTE XIII. .... ELECTRICITY. I. P oints preferable to knobs for defence of buildings ; why points emit the elechic fluid; diffufion of oil on water; mountains are points o; the eart',·- globe; do they produce afcending currents of air? 2. Fairy-rings explained; advantage of paring and burning ground. Non XIV ..... BuDs AND BbLBs. A TnEE is a fwarm of individual plants; vegetables are either oviparous or VIVlparous ; are all annual productions like many kinds of infetls ; hybernacula; a new bark annually pFodueed over the old one in trees and in fome herbaceous plants, whence ~ their roots feem end-bitten; all bulbous roots perifh annually; experiment on a tuliproot ; both the leaf-bulbs and the flower-bulbs are annually renewed. NoTE xv ..... SOLAR VoLCANOS. THE fpots in the fon :ne cavities, fomc of them fom· thoufand miles deep and many• times as broad ; internal parts of the fun are not in a fl:ate of combuflion ; volcanos vifi ble in the fun; all the planets together are Jefs than one fix hundred and fiftieth part of the fun; planets were ejeCl:ed from the fun by volcaMs; many reafons !hewing the probability of this hypothefis; Mr. Buffon's hypothefis that planets were firuck off from the fun by comets ; why no new planets are ejected from the fun; fome comets and the georgium fidus may be of later date; Sun's matter decreafed; Mr. Ludlam's opinion, . that it is poffible the moon might be pmjeCl:cd from the earth. NoTE XVI. .... CALCAREous EA.RTH . H 1 GH mountains and deep- mines replete with !hells; the earth's nucleus covered · with limefione; animals convert water into limeftone ; all the calcareous earth in the world formed in animal and vegetable bodies ; folid parts of the earth increafe ; the water decreafes; tops of calcareous mountaim diffolved; whence fpar, marbles, chalk, ftalactites; whence alabafl:er, fluor, flint, granulated limefl:one, from folution of their angles, and by attrition; tupha depofited on roofs; limcftones from !hells with animals . |