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Show BUDS AND BULBS. NoTE XIV. From the obfervat ions and drawings of various kinds of b~lbou~ roots at di~~:~~ · f tl ·r oro,,· J 1 fent me by a yollna lady of nice obfervatJOn, 1t appears pr tltl1CS 0 l CI IS l ' b . • . B dl M"\1 that all bulbous r ots properly fo called perifh annually m ti11S clu~ate: ra cy' I ~r' and the Author of Spetl:acle de Ia Nature, obferve that the tulip annually renews tlS bulb, for the ft alk of the old flower is found under .the old dry coat but on .the outftde of the new bulb. This brge new bulb is the flowenng bulb, but befides thts there are other [mall new bulbs produced between the coats of this large one but from the fame cande:<, (or circle from which the root-fibres fpring ;) thefe fma~l bulbs are leaf-bearing bulbs, and renew themfelves annually with increafing fize till they bear flowers. Sh k r 11 Mifs ___ favoured me with the following curious experiment: e too a una tulip-root out of the earth when the green leaves were fufficiently high to {how the flower, and placed it in a glafs of water; the leaves and flower foon withered and the bulb became wrinkled and foft, but put out one [mall fide bulb and three bulbs ~eneath defcending an inch into the water by procefies from th~ caudex, th~ old bulb m fome weeks intirelv decayed ; on diffetting this monfier, the mtddle defcendmg bulb was found by its procefs to adhere to the caudex and to the old flower-fiem, and the flde one5 were feparated from the flower-fiem by a few fhrivelled coats but adhered to the caudex. vVhence fhe concludes that thefe Jail: were off.fets or leaf-bulbs which !hould have been feen between the coats of the new flower-bulb if it had been left to grow in the earth, and that the middle one would have been the new flower-bulb. In fome years (perhaps in wet feafon s) the ftorifls are laid to lofe many of their tulip-rgots by~ fimilar procefs, the new leaf-bulbs being produced beneath the olJ ones by an elongauon of the caudex without any new flower-bulbs. . By repeated diffettions 01e obferves that the leaf-bulbs or off~fets of tuhp, crocus, gbdiolus, fritillary, are renewed in the fame manner as the flowenng-.bulbs, contrary to the op inion of many writers; this new leaf-bulb is formed on the Infide of the coats from whence the leaves grow, and is more or lefs advanced in fizc as the outer coats and leaves are more or lefs fhrivelled . In examining tulip, iris, hyacinth, hare-bell, the new bulb was inv:uiably found bflween the flower-fiem and the bale of the innermoll: leaf of thofc root s which had flowered, and incloferl by the bafe of the innermofi. leaf in thofe wots which had not flowered, in both cafes adhering to the caudex or flelhy circle from whi ch the root-fibres fpring. H ence it is probab le that the bulbs of hyacinths are renewed annually, but that this is performed from the camlcx within the old bulb, the outer coat of which does not fo !hrivel as in crocus :md fri tillary and hence this change is not fo apparent. But I belteve as foon as the t:lower is advanced the new bulbs may be feen on di{feClion, nor does the annual increa fe of the Gze of the root of cyclamen and of aletris capenfis militate againfl: this annual renewal of them, fince the leaf-bulbs or off-fets, as defcribed abovc 1 :~re increafed in flze as they are annually renewed. See note on orchis, and on anthoxanthum, in Vol. l I. of this work. NOTE XV.-SOLAR VOLCANOS. From the deep craters qf his realms of fire 'The whirling Jun this ponderous planel hurl' d. CANTO II. I. I 4· DR. ~LEXA~DER. WILSON,. Profeffor of A!lronomy at Glafgow, publifhed a p~pe: 111 the Phtlof~p.htcal Tran:a cb ons for 1774, demonfirating tbat the fpots in the fun s ddk are real cavtttes, excavatiOns through the luminous material, which covers the other parts of the fun's fur face. One of thefe cavities he found to be about 4000 miles deep and many times as wide. Some objeCtions were made to this doCtrine by M. Dt! la Lande in the Memoirs of the French Academy for the year I7J6, which however hav.e been ably anfwered by Profeffor Wilfon in reply to the Philof. Tranf. for 1783. Ketl o~ferves, in his Allronomical Lettures, p. 44, " We frequently fee fpots in the ~un whtch are larger and broader not only than Europe or Africa, but which even equal, 1f t.h~y do not exceed, the furface of the whole terraqneous globe." Now that thefe cavlltes are m.ade in the fun's body by a procefs of nature fimilar to o.1r earthquakes doe.s not .feem 1mprobable on feveral accounts. I. Becaufe from this difcovery of Dr. W dfon 1t appears that the internal parts of the fun are not in a !late of inflammation or of ejeeting light, like the external part or luminous ocean which covers it; and hence that a greater degree of heat or inflammation and confequcnt cxpanflon or explofl on may occafionally be produced in its internal or dark nucleus. 2. Becaufe the folar fpots or cavities arc frequently i~1C rea fc d or diminifhed in !izc. 3· New ones are often produced. 4· And old ones vani!h. 5· Becaufe there are brighter or more luminous parts of the fun's difk, called facul:e by Scheiner and H evcliu s, which would feem to be volcanos in the fun, or, as Dr. Wilfon calls them, "eruttations of matter more luminous than that which covers the fu n's fmL:ce." 6. To which may be added that all the planets added together with their fatdli tcs do not amount to more th an one fix hundred ami fiftieth part of the mafs of the ft tn accordi ng to Sir Ifaac N ewton. Now if it could be fuppofetl that the pbnets were originally thrown ont of the fun by larger fun-qu akes than thole frequent ones which occ~fion thefe fpots or excavations above mentioned, what would happen 1 I. According to the obfcrvations and opinion of Mr. Herfchel the fun itfelf and all its planets are moving forwards round fome other centre with an unknown velocity, whi ch may be of opake m ~. tter correfponding with the very antient and general idea of a chaos. Whence if a ponderous planet, as Saturn, could be fuppofed to be projected from the fun by an explofion, the motion of the fun itfelf might be at the fame time difiurbed in fuch a manner as to prevent the pl:111et from falling again into it. 2. As the fun re\ uiles round its ewn axis its form mufl: be that of an oblate fpheroid like the earth, at d therefore a body proj eCted from its furface perpendicularly upwards from that furface would not rife perpendicul arly from the fun's centre, unlefs it happened to be projeeted exaetly from ei ther of its poles or |
