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propagation of small and early bearing trees: in fact, the success of layers, slips, pipes, &c., all depend upon this peculiar power. The complete inversion of a tree, as of a willow, gives an excellent example of the metamorphosis of buds, for the roots of the trees will become covered with leaves and flowers; and the branches planted in the earth will develope roots. In pear, apple, and other fruit trees, in which the buds which will produce leaves are, by a practised eye, easily distinguished from those which will produce flowers and fruit, the latter being called bearing buds, the conversion of the one into the other is continually effected by art. "A friend of mine had three pear trees growing against a wall, having an eastern aspect, and a good deal shaded; these trees year after year were luxuriant as to leaves, but never blossomed; the groom having tethered a horse to one of these, the animal gnawed it three parts round, denuding it of bark for the space of several inches; that tree, and that alone, the succeeding summer bore fruit; and a practice similar to this is frequently resorted to for the conversion of leaf into flower buds: for so easily can they be distinguished, that I am told it is no uncommon thing in the cyder counties for the crop of apples to be bargained for and sold merely from the promise of the buds." The physiology of this conversion Mr. B. attempted to explain, by the hypothesis that every bud was a distinct individual including, potentially at least, roots, leaves and flowers, but that in certain circumstances only were the several organs developed; and that when a tree is inverted, and its roots evolve leayes, and its branches roots, it is not a mutation of leaves into roots, but the developement of that part which, under other circumstances, would have been obsolete, and in the obliteration of that which would have been developed; and the › same of the leaf and flower buds. As examples of the metamorphosis of seeds into gems, specimens of proliferous flowers were shewn, and the separation of buds, as in lilium bulbif., &c. was instanced as an approximation of these to the character of seeds. An example was shewn of this spontaneous separation of a bud or tumor in a cedar tree.

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Of the acclimation of plants many instances were given, and specimens on the table of plants which, having migrated from various countries, are naturalized in very different latitudes; to this it would seem that we owe the chief of our vegetables, fruits, and flowers. sud bib Aca

...Of the extraordinary or fortuitous developement, better called til sme out to han sno yliam bir bubo ... Debt & chega at vit div

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the casual metamorphosis, time allowed but one section to be referred to, viz., the first or simplest grade relating to excess of 'growth, either in the whole or particular parts of certain plants, the metamorphoses occurring in monstrous, mule, and mongrel plants being reserved for another opportunity.

Plants in their wild state, observes Wildenow, remain pretty constant in their appearance; but no sooner are they domesticated, than, like animals, they begin to change their size, their colour, and their taste.

***Of increase in size many instances were shewn; e. g. leaves of potentilla anserina upwards of two feet long; of horse chesnut, twenty-two inches across, &c. &c. The grass called fiorin (agrostis stolonifera) in barren soils and on the sea-shore seldom exceeds three or four inches in height, but in fertile soils it is so greatly changed as to produce from 16,000 to 18,000lbs. weight of hay per Tacre, and two acres and a half have yielded ten tons of hay in one year; indeed, Dr. Maton collected specimens about seven feet long at Orcheston, and likewise, at the same place, found poa trivialis nearly ten feet long. The ordinary height of meadow clover may be about ten or twelves inches, but it sometimes reaches four feet, &c. &c. The chief object of the lecturer seemed to be to shew the complete dominion that man possessed over the fruits of the field, and that so changed had they become that many might, with some latitude of expression, be said to be made by man. Thus, wheat is no where to be found wild, or, if found, as hath been asserted, in Thibet, it is so altered, that the most accomplished botanists doubt the legitimacy of the descent, so far superior is the offspring to the reputed stock. Who, in the wretched sloe, would recognise the parent of our most luscious plums? or think our most luxuriant apples the offspring of the austere and verjuice crab? The cat's head and some Normandy apples will singly weigh from eight or ten ounces to one pound, which is often as much as the entire crop of the ancestral crab. Of this increase in produce, Withering records an excellent example. At Home Lacy, says this author, there grows a pear tree, which, from successive layers, hath spread hover nearly a quarter of an acre, and has yielded for many years sufficient fruit to form annually from twelve to sixteen hogsheads of perry... Who, in the almond's rough and leathery coat, would recognise the rudiments of the luscious peach? yet not unfrequently this acquired luxuriance is checked, and the original state hof almond is found on the same tree, nay, even on the same branch with the factitious peach; occasionally one half of the same fruit

retains the acquired character of peach, while the other degenerates to the almond state. Similar changes are also sometimes met with in apples, one half being small and austere as the parent crab, the other remaining an undegenerated nonsuch. "In our garden at Laleham, a few years ago, a single peach tree produced the amazing crop of 130 dozen fine peaches, besides a vast quantity thinned away in the early part of the season."

Specimens were shewn of many garden vegetables in their uncultivated state, that they might be contrasted with such as are now brought to the table; e. g. the apium graveolens, thin, dark green, and very acrid, would not be known as our common celery, when, by cultivation, the leaf stalks have grown upwards of five feet long, and two inches in diameter. Petioles of rhubarb have been cut nearly three feet long by six inches in circumference; and twelve, when trimmed for the market, weighed upwards of a quarter of a hundred. Specimens of the wild cabbage were shewn, not weighing, leaves, flowers, and all, quite an ounce; now these contrast finely with the offspring, cauliflower, the blossoms of which will weigh several pounds, and with the large cabbages, the leaves of which have been known to exceed sixty pounds in weight; an account of one has been published which measured five feet round.

Similar metamorphoses were illustrated by wild specimens on the table of the lecturer,-asparagus, seacale, parsnip, carrot, &c. The latter roots are small and woody; but when cultivated increase so much in size and succulence, that they have been known between two and three feet long by more than one foot round, and weighing upwards of four pounds; the potatoe, also, when growing wild in Chili, and in unfavourable situations, is small as a common marble, and very bitter; but when in proper soil and cultivated, a single tuber will weigh from one to two, or even, as hath been stated, nearly three pounds.

The lecturer shortly alluded to the absurd doctrine at one time prevalent, of the conversion of one plant into another; as of wheat into cow-wheat, darnel into oats, &c. &c. and shewed that although cultivation might improve, and subsequent neglect deteriorate, the degeneration was only a return to that state from which the variety had been fortuitously removed. He concluded by observing, "Doubtless, many of the circumstances to which I have referred already were familiar to many of my audience. Many of the metamorphoses on which I have had to comment are passing continually before your eyes; many of the details of these changes are daily sounding in your ears: but they are not the less curious, because

they are common, nor the less worthy notice because they can by all be known; their certainty rather than their mystery, their fre quency rather than their rarity to me, are gages of their importance; though some persons may not impossibly feel as much astonished, that changes so common and familiar should be dignified by the term metamorphosis, as Molière's Bourgeois Gentilhomme was astonished to find out, that he had all his life, although unconsciously, been talking prose."

February 6th.

In the library were a series of cosmospheres and cosmospherically mounted globes, invented by Major Muller, who was present to explain their principle. M. Nobili's exceedingly sensible galva-. nometer was also on the table, with its accompanying portable apparatus, by which the testing powers of the instrument are applied. Mr. Nobili was present to explain it.

In the theatre, Mr. Green delivered a lecture on the study of ancient coins, which he has since published.

February 13th.

A variety of interesting objects of art and antiquity were upon the library table.

In the lecture-room Mr. Faraday explained Mr. Brown's discovery of apparently active molecules in bodies.

A brief account of Mr. Brown's results has already been given in our Journal. Mr. Faraday, by means of drawings and specimens, gradually developed the path by which Mr. Brown was led to the singular conclusions at which he has arrived; the care that he took to test the appearances he met with; and the state of his opinions at present, which in public have been much mistaken.

First engaged in examining pollen and the particles from its grains, Mr. Brown found that all solid matter insoluble in water, with very few, if any exceptions, when reduced to powder and suspended in water, gave particles which exhibited, under the simple microscope, peculiar motions. One kind of motion was progressive, the particle advancing forwards more or less rapidly, and changing places with the neighbouring particle; another kind was a vibratory action, in which the particle seemed rapidly to oscillate backward and forward about an axis nearly vertical; at other times, the particle would advance, then recede, then advance; and in that manner oscillate, moving at such times over a space equal to a half

New Series, vol. iv. p. 234,

or a whole diameter, two or three complete vibrations occurring in a second. With particular substances, linear arrangements of particles were frequently seen to move, the appearance then resembling a twisting or vermicular motion. The molecules usually appeared of a rounded form, and had been estimated by Mr. Brown and others, as being from the to the of an inch in diameter, but in later observations minute angular particles were distinctly seen in motion.

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Mr. Faraday stated that Mr. Brown had endeavoured in every possible way to justify by experiment the reference of these motions to some known cause, but had failed in doing so. Evaporation had been prevented by inclosing the fluid and particles, sometimes by plates of mica, sometimes by a film of oil, and sometimes by other means; but still the motion went on. That they were not due to ordinary currents existing in the fluid was easily proved by the great difference in character of the motion resulting when currents were purposely occasioned. That electricity excited by friction or otherwise in known ways was not the cause, was concluded from the circumstance that this motion continued unabated for hours together, whereas there is every reason to believe, according to what we know, that a difference in electric state would soon have been equalized, and the particles have come to rest. Other explanations had in turn been shewn, by varying the mode of experimenting, to be insufficient; and naturally averse as Mr. Brown was to leaving the subject in this state, he, after many months' investigation, published the discovery of these motions without pretending to be able to account for the cause. Not asserting that a new power of matter was concerned; not denying that the powers with which we are acquainted might not be sufficient to originate the motion; but thinking it much more philosophical to acknowledge ignorance as to the mode of action in these cases, and to suspend the judgment, than, by the assumption of an opinion, which must have been hypothetical, run the great risk of shackling the mind by the admission of error for truth.

Mr. Faraday then referred to the influence of this discovery of Mr. Brown (which all must acknowledge as true in fact, whatever their theories may be) upon the hypotheses which have been at various times promulgated respecting different points in vegetable physiology, as the impregnation of the ovulum, &c. The discovery of active molecules obtainable from matter which could not be vital," as glass, flint, &c. &c. overthrows all reasoning founded upon the vitality, or even presence of particles which have been supposed to

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