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Show [ 122 J plieJ by fup er ior currents; 2. The whole atrnofphere increafed in q~antity by air fet at · f · b' 1· ns '1n the polar li be rty rom 1ts com 111a 10 ' ci rcl es. Soutb-e. n'.n/' wm.d s conll fl: .o f 11orth · d d · hack 11Win S riVe n • H. r01·th -we'.l/l' winds confi fl of fou th-we fl wmcl s unven. back , north-weft win rls of America bring frofl:; owing to a vertical fpiral eddy of a1r between _the eafl:ern coafl: and the Apalachi::tn mountain s ; hence the greater cold of N~ rth Ar:n e n c~. 'Trade-winds ; air over the L ine al ways hotterthan at the tropics ; trade-wwds gam th~ ueafl: erly direction from th e g reater velocity of the earth's fu rface at the l i~1 e ; not fu ppl1ccl y fuperior curre nts: fuppl ied by decompofed water i ~ the fun's great ligh t ; ~· Becaufc there are no cotllhnt rai ns in the traCt: of the trade- w111Js; 2. Becaufe there IS no condenfible v::~pour above three or four miles high at the line. 111/onfoon.r and .tornadoes ; fume places at the t ro pic become warmer when the fun is vertical than at the lme , hence the air ::&ends, fupplied on one fide by the north- eafl: win ds, and on the other by the fouth-well; "'·hence an afcc nding eddy or torn ado, ra ifl ng w::~ter from the fea, or fand from the defcrt and inceffant rains; a ir dimin iOJcu to the northward produces fout !1- well: winds ; to;nadoes from heavier air above fi nking through lighter air below, which rifes th rough a perforation; hence trees are thrown down in a narrow line of twenty or forty yards broad, the fea rifes like a cone, with great rain and lightning. L and andjea breezes ; fe a lefs heated than l:l.nd; tropical iOands more heated in the day th an the fea, and are cooled more in the night. Conclujion; irregular winds from other caufes:; only two original winds north and Io uth; different fo und~ of uonh-eaft and fouthwefl: wi nds ; a Bear or Dragon in the arctic circle that [wallows at times and difembogues again above one fifteenth part of the atmofphere; wincl-infl:rumcnts ; recapit ulation. NoTE XXX IV .. . .. V EGETABLE PERSPIRATION. P uRE air from Dr. Priefll ey's vegetable matter, and from vegetable leaves, <zwing to dccompofi tion of water; the hydrogene retained by the vegetabl es; plants in the !hade are tanned green by the fun's light; animal fkins are tan11ed yel low by the retention of hydrogene ; muc11 pure air from dew on a funny morning ; bleaching why fooner performed on cotton than linen ; bees wax bleached; metals calcined by decompofttion of water; oi1 bleached in the light becomes yellow again in the dark ; nitrous acid coloured by being expofed to the fun; vegetables perfpire more than animals, hence in the funfhine they purify air more by their perfpiration than they injure it by their refpiration ; they grow fafl:efl: in their !leep. NoTE xxxv ..... VEcETABLE PLACE NTATioN. B uo s the viviparous offspring of vegetables; placentation in bulbs and feeds; placentation of bud~ in the roots, hence the rifing of fap in the fpring , as in vines, ·birch, which ceafes as foon as the leaves expand; produCt:ion of the leaf of Horfechefnut, and of its new bud; oil of vitriol on the bud of Mimofa killed the leaf alfo; placentation fhcwn from the f wcetnefs of the f.1p ; no umbilical artery in vegetables. [ 123 1 N OTE XXXVI. .. :.VEGETABLR CIRCULATION. Buns fet in the ground will grow if prevented from bleeding to death by a cement; vegetables require no mufclcs of locomotion, no fl:omach or bowels, no general fyfl:em of veins; they have, I. Three fyfl:ems of abforbent veffels; 2. Two pulmonary fyfl:ems; 3· Arteri al fyfl:em s ; 4· Glands ; 5. Organs of reproduCt:ion; 6. Mufcles. I. Abforbent fyfl:em evinced by experiments by coloured abforptions in fig-tree and picris ; call ed air veffels erroneoufly; fpiral flructure of abforbent veffels; retrograde motion of th em like the throats of cows. I L Pulmonary arteries in the leaves, and pulmon ary veins ; no general fyfl:em of veins lhewn by experiment ; no heart ; the arteries act like the vena portarum of the liver; pulmonary fyfl:em in the petals of flowers; circulation owing to Jiving irritability; vegetable abforption more powerful than :i!n imal, as in vines ; not by capillary attraB:ion. NOTE XXXVIl . .. .. VECETABLE RESPIRATION. I. Leaves not perfpiratory organs, nor excretory ones; lungs of animals. I. Great fu rfaces of leaves. 2. Vegetable blood changes colour in the leaves; experiment with fpurge; with picris. 3· Upper furface of the leaf only acts as a refpiratory organ. 4· Upper furface repels moifl:urc; leaves laid on water. 5· Leaves killed by oil like infects ; mufcles at the foot-flalks of leaves. 6. Ufe of light to vegetable leaves; experiments of Pricfl:ley, Ingenhouz, and Scheele. 7· Vegetable circulation ftmilar to that of fi01. II. Another pulmonary fyfl:em belongs to flowers; colours of flowers. I. Vafcular firucture of the corol. 2. Glands producing honey, wax, &c. perilh with the corol. 3· Many flowers have no green leaves attending them, as Colchicum. 4· C orols not for the defence of the fl:amens. 5. Corol of Helleborus Niger changes to a calyx . 6. Green leaves not neceffary to the fruit-bud; green leaves of Colchicum belong to the new bulb not to the flower. 7· Flower-bud after the corol falls is fimply an uterus; mature flowers not injured by taking off the green leaves. 8. Inofculation of vegetable veJfels. NoTE X XXVIII. .... VEGETAD LE I MPREGNATION. Seeds in broom. di fcovered twenty day~ before the flower opens ; progrefs of the feed after impregnation; feeds exifl: before fec undat ion; analogy between feeds and eggs ; progre::fs of the egg with in the hen ; fpawn of frogs and fi01cs ; male S::~!amander; marine plants project a liquor not a powder; feminal flu id diluted with water, if a fl:imulus only ? Male ::tnd female influence neceffary in animals, infeCt:s, and vegetables, both in production of feeds and buds ; does the embryon feed produce the furrounding fruit, li ke infeCts in gall -nuts ? |