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The average height of the barometer is about thirty inches.

Ditto ditto thermometer, about thirty-nine degrees.

In the first Week.—Blue titmouse (tom tit) Partis ccerulens, chirps; marsh titmouse, (Pants pahtstris,) utters its two sharp notes, resembling the sharpening of a saw; bees, {Apia mellifera,) appear; gnats, {Gulex pipiens,) float in the sun-beams; and insects hover about sunny banks; moles, {Talpw,) throw up their heaps; brown owl, {Stri.v ulula,) whoops; and song thrush, or throstle, {Turdus musicus,) sings.

Second Week.—Turkey-cock, {Meleagris gallo-pavo,) gobbles and struts; yellow-hammer, (Emberiza flaw,) sings; sulphur butterfly, (Papilio rhamni,) appears; goose {Anas a user,) lays; sheep {Otis aries,) drop their lambs; blackbird, {Turdus merula,) sings.

Third Week.—Rooks, {Corttts frugilegus,) pair; raven, {Corvus corax,) builds; partridges, {Tetrao cinerea,) pair; house sparrows, {Fringilla domestica,) chirp and begin to build; chaffinch, {Fringilla coslebs,) sings; green woodpecker, (Picus viridis,) clamours and laughs.

Fourth Week.—Viper, {Coluber borus,) appears; goldfinch, {Fringilla carduelis,) sings; pheasant, (Phasianus gallus,) sets; wood and field-larks, {Alauda, arborea et arvensis,) sing; and the curlew, {Charadreus Oedicnemus,) utters its quick, short note.

MARCH.

SECTION I.
SCIENCE OF GARDENING.

Part I.

WATER.

Inquiry into the Nature of Water.

2. What is water? A more important question in natural history, and one, the solution of which involves more stupendous phenomena, can scarcely be proposed: it is an inquiry into the nature of that fluid which, under the familiar term water, comprises oceans, seas, lakes, rivers, springs; in a word, all that constitutes the aqueous portions of the globe. To this important question, however, a ready answer would, within little more than half a century from the present time, have been unhesitatingly returned: it would have been said, that " water is a simple element," for such it had always been considered; "one of the four elements, entering into the composition of most bodies; a fluid menstruum, a ready solvent of many substances, but itself incapable of decomposition. Yet its decomposition has been going on from the remotest period of time, unthought of and unobserved. This is a fact, as Lavoisier remarks, which proves that in chemistry, as well as in philosophy, "it is extremely difficult to overcome prejudices imbibed in early education, and to search for truth in any other road than the one we have been accustomed to follow."

The inquiry into the true nature of water includes matter of exceeding interest and curiosity; and by comparing a variety of quotations, which I select from writers of acknowledged authority, the reader will be enabled to form a tolerably correct idea of the present accredited theories. To these quotations will be added such remarks as shall tend to explain and apply the electrical theory advanced at Number 66, and to demonstrate the certainty and importance of electric agency, in the induction of the striking phenomena which accompany the decomposition and formation of water.

It may be fairly presumed, that the most valuable discoveries in science have originated either in conjecture, or in what is termed chance. By submitting to the test of experimental scrutiny conjectures on subjects not absolutely capable of being confirmed by actual experiment, important discoveries may be effected and philosophical truths established: thus the mind of Newton, reasoning from analogy, suggested the combustible nature of the diamond; and thus au observant eye, viewing one particular phenomenon, may bo led to determine the precise nature or cause of some other phenemena connected therewith, which had puzzled the most renowned philosophers of the age. An almost insurmountable obstacle to the advance of philosophical inquiry has heretofore been raised by that implicit deference which is usually paid to the authority of great names. Thus the phlogistic theory of Stahl maintained its ascendency for more than fifty years, although abounding with the most palpable contradictions; for it was received and supported by the most eminent chemists of Europe, But science was then in the hands of the few learned; it is now spreading through the ranks of the inquiring many; and these, it is to be hoped, while they respect the authority of great names, will never henceforward take that for granted, which can by any means be submitted to the scrutiny of scientific experiment. It is to such scrutiny,—liberal, because scientific,—that I submit any conjectures which I may advance in opposition to received opinions and accredited theories.

M. Compound nature ofwater.—About the year 1781, the discovery of the decomposable nature of water was detailed in the Memo ires of the French Academy: who the discoverer really was, has been contested, and it is still doubtful. Dr. Priestley, there is reason to believe, first effected the decomposition of water; but the appreciation of the real and determinate nature of the discovery is usually ascribed to Mr. Cavendish.

Little more than half a century has elapsed since the idea of the simple, elementary nature of water has been abandoned. Subsequently, however, to the actual discovery, innumerable experiments, both analytical and synthetical, have proved to a demonstration the compound nature of water, and have appeared to determine, pretty accurately, the proportions of its constituents: for it has been found, that if two parts of hydrogen gas be ignited and burnt, with due precaution, in a vessel containing one part of oxygen gas, both calculated by measure, and not by weight, the product will be pure water. To effect the union of the two gases, it is usual either to pass an electric spark through them, or to kindle the hydrogen first by actual fire, and then to introduce the jet pipe from which it issues, into a globular glass vessel, containing the oxygen gas; but considerable caution is required, as the experiments are sometimes productive of the most violent explosions. In fact, they should not be attempted by inexperienced persons, as dangerous consequences might ensue.

94. Composition of water.—1st. According to Lavoisier, {Elem. c. 8. exp. 3,) it appears, that by passing the steam of boiling water through a glass tube, heated to redness in a furnace, and containing 274 grains of soft iron turnings, 100 grains of water having been decomposed, 85 grains of oxygen had combined with the iron, so as to convert it to the state of black oxide; and 15 grains of a peculiar inflammable gas were disengaged. "From all this," says he, "it clearly follows, that water is composed of oxygen, combined with the base of inflammable gas, in the proportion of 85 parts by weight of the former, to 15 parts of the latter." Such are the words of the father of modern chemistry.

2nd. According to Parkes, {Bud. No. 108,) "water is composed of 88 parts by weight of oxygen, and 12 of hydrogen, in every 100 parts of the fluid." "Water is found to be a compound of 1 part hydrogen, and N parts oxygen, by weight; this will give in the 100 parts the proportions of nearly 1 If of hydrogen, and 88^ of oxygen. If the gases are estimated by their measure, water will be found to be composed of two measures of hydrogen, and one of oxygen." {Ibid note.)

The same author, however, in his Chemical Essays, (Water, vol. ii. p. 256.) gives other proportions of the constituents of this fluid; and therein he accords with Lavoisier. "Water is composed of oxygen and hydrogen, in the proportions of 85 parts by weight of the former, and 15 of the latter. These are what are deemed the usual proportions, but they cannot be considered as absolutely and undeniably correct; because the quantity of aqueous vapour which the gases usually contain, renders it difficult, if not impossible, to produce an accurate estimate. Some experiments of Putter seem to prove, that frozen water contains a less proportion of oxygen." By the "atomic theory," or rule of definite equivalents, hydrogen being assumed the standard unit, or 1, and oxygen being eight times heavier or 8, 9 is the atomic weight of water; then, as 9 : 8 : : 100 to 88-888; the hydrogen, therefore, will be represented by lTlll, iu every 100 parts.

3rd. "If the metal called potassium, be exposed in a glass tube to a small quantity of water, a violent action will ensue; an elastic fluid will be disengaged, which will be found to be hydrogene; and the same effects will be produced upon the potassium as if it had absorbed B small quantity of oxygene; and the hydrogene disengaged, and the oxygeije added to potassium, are in weight as 2 to 15: and if 2 in volume of hydrogene, and 1 in volume of oxygene, which have the weights of 2 and 15, be introduced into a close vessel, and an electric spark passed through them, they will inflame and condense into 17 parts of water."—{Davy's Agric. Chem. Lect. v., p. 191.)

It may be here proper to observe, that some have suggested the probability of earthquakes having been occasioned by the decomposition of water through the agency of metals, particularly those of potassium and sodium, both of which were discovered by Sir Humphry Davy. The eruption of Vesuvius, in 1822, was accompanied by a discharge of chloride of sodium, (common salt.) Rock-salt and saltmines may possibly, therefore, have been produced by the decomposition of water in former ages, through the agency of the metal sodium.

85. Water may be decomposed by the electric spark, but with some difficulty, unless by an apparatus of a peculiar construction; but with the voltaic (i. e. galvanic) apparatus, the process of decomposition may be effected with the utmost facility. One of the most luminous experiments with the voltaic electricity, will now be described as concisely as possible; it is very frequently exhibited by public lecturers, and the figure annexed is taken from the first volume of the Mechanic's Register, p. 879.

Fig. l.

[graphic]

Let two glass tubes, A H (fig. 1), be filled with pure water, and then inverted into the two cups c n, each containing water in sufficient quantity to admit of the complete immersion of the ends of the tubes, so as to keep them full of water, N P are platinum wires, each furnished with a ring at the upper extremity; they each pass through a cork at the top of the tube, and are carefully secured with cement, so as to render the junction perfectly air tight. The two cups are connected by means of the bent tube r, which is first filled with water, or a coloured fluid, and then inserted, one end in each cup, the two orifices being secured by the fingers, till immersed, when the

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