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cation with the copper, is surrounded copper. No notice was taken of this by a solution of salt in water. Now by at the time; but some days after, when this instruinent, a species of electricity, examining the copper plate, he found

called voltaic, from Volta, its discoverer, that crystals were formed upon all parts t is developed; and thus many very curious of it excepting where the varnish had ? and interesting experiments may be fallen. “I at once saw," he says, “that

made. For instance; if wires proceed. I had it in my power to guide the meing from the binding screws z', c', which tallic deposition in any shape or form

are connected with the metallic plates, I chose, by a corresponding application .. be brought into a particular position of varnish or other non-metallic sub

near a magnet, the electricity conveyed stance.”. Experiments were then imby them will cause it to deviate from its mediately commenced, and have led to magnetic position, chemical substances important results. may be decomposed, and light and heat The first attempt was made in the be given out.

following manner:-A piece of thin Among the various experiments which copper was covered with a cement of have been performed, that of producing bees wax, resin, and a red earth while crystallized mineral substances is not hot; and the experimenter scratched

the least interesting. To accomplish the initials of his name upon it, when I this, Mr. Cross, the gentleman who first cold, taking care to clear away all the

made the experiments, and all other varnish, and leave the copper exposed. observers, had found it necessary to be- To this plate, a piece of zinc was atgin with a metallic nucleus ; to provide tached by a copper wire, the former in fact a base, upon which the crystal being immersed in a solution of sulphate

lization could be effected. But at the of copper, the latter in a solution of salt. fra Liverpool meeting of the British As- The vessel in which the experiment was

sociation, in September, 1837, Dr. performed, was a cylindrical glass, Golding Bird ventured' an assertion, within which was placed a gas glass which has not yet been proved, that closed at one end by plaster of Paris, of

crystals of pure copper could be pro- a thickness of about three quarter of an u duced without any nucleus for their form- inch. The solution of salt was thus pre

ation. Mr. Spencer seems to have made vented from mixing with the solution of some careful experiments to ascertain if sulphate of copper; and yet the substance this could be done, and came to a con- was sufficiently porous to allow the clusion which all other scientific men have electro-chemical action to go on. arrived at "that no metallic crystal- | few hours, the action commenced, and lization will take place, unless a me- Mr. Spencer was delighted to see that tallic or metalliferous nucleus be pre- a bright metal was being deposited on sent." These experiments, however, the parts made bare by the scratches, were the means of leading him to the and that no other portions of the plate happy discovery which we are about to were in any way acted upon. It may explain ; and it may therefore be neces- easily be imagined that the mind of the sary to give an account of the apparatus discoverer was agitated by many hopes that was employed. The instrument and fears, expecting on the one hand consisted of a small piece of zinc and to add a new and invaluable invention copper connected by a wire of the latter to the arts, and fearing on the other metal, but separated from each other that his results might be rendered altoby a thick disc of plaster of Paris, which gether useless by some unexpected difdivided the glass vessel that contained ficulty. The two questions which seemed them into two parts.

The cell which to demand immediate reply were-Whecontained the copper was filled with a ther the deposition would retain its hold solution of the sulphate of that metal

, on the plate, and whether it would be perhaps better known to our readers as of sufficient strength to bear working if green vitriol, and that holding the zinc applied to a useful purpose.

Beside with a solution of common salt. To these, there was another point to be prevent any action taking place on the decided—the possibility of producing lines wire which united the copper and in sufficient relief to be printed from. zinc, it was covered with sealing-wax In the course of experiments, made varnish ; but when applying this resin- with a view to determine these imous compound, Mr. Spencer accident- portant principles, a serious difficulty ally dropped a small quantity on the l arose, which was accidentally overcome.

In a

says Mr.

manner.

“ There was one important, and to me after to describe: “I then gave a plate discouraging circumstance,

a coating of cement, to a considerable Spencer, "attending these experiments, thickness, and sent it to an engraver ; which was, that when I heated the but when it was returned, I found the plates to get off the covering of cement, lines were cleared out so as to be wedgethe meshes of copper net work” (for shaped, leaving a hair line of the copper it was in the form of net work that he exposed at the bottom, and a broad was depositing the metal) “invariably space near the surface; and where the came off with it. I at one time ima- turn of the letters took place, the top gined this difficulty insuperable, as it edges of the lines were galled, and renappeared to me that I had cleared the dered rugged by the action of the gracement entirely from the surface of the ver. This, of course, was an important copper I meant to have exposed; but that objection, which I have since been able there was a difference in the molecular to remedy, in some respects, by an alarrangement of copper prepared by heat, teration in the shape of the graver, and that prepared by voltaic action, which which should be made of a shape more prevented their chemical combination. resembling a narrow parallelogram than However, I then determined, should this those in common use.: some engravers prove so, to turn it to account in another have many of their tools so made. I

did not put this plate in action, as I saw It happened, however, that upon the that the lines, when in relief, would examination of the results of one ex- have been broad at the top and narrow periment, a part of the copper depo. at the bottom. I took another plate, sition formed upon a coin adhered so gave it a coating of the wax, and had tenaciously that it could not be removed; it written on with a mere point. I de“indeed a chemical combination had posited copper on the lines, and afterapparently taken place. This,” says wards had it printed from.” the discoverer, “ was only in one or two We have already mentioned an exspots, on the prominent parts of the periment in which a piece of copper (on coin. I immediately recollected that on which had been drawn lines in the form the day I put the experiment in ac- of net work) was used. Much difficulty tion, I had been using nitric acid for was experienced in forming this design another purpose, on the table I was upon the copper, so as to expose the operating on; and that in all proba. metal; for when the cement was soft, bility the coin might have been laid the lines were pushed into each other, down, where a few drops of the acid and when of a harder texture, the interhad accidentally fallen. I then took a vening squares broke away from the piece of copper, coated it with cement, surface of the plate. One difficulty, made a few scratches on its surface un- therefore, still remained, and it was til the copper appeared, and immersed the discovery of a proper cement or it for a short time in dilute nitric acid, etching ground, one w which should be until I perceived by an elimination of capable of being cut to the required nitrous gas, that the exposed portions depth, without raising what is techniwere acted upon sufficiently to be slightly cally called a burr, and at the same time corroded. I then washed the copper in of sufficient toughness to adhere to the water, and put it in action as before de- plate, when reduced to a small isolated scribed. In forty-eight hours I ex- point, which would necessarily occur in amined it, and found the lines were en- the operation, which wood engravers tirely filled with copper. I applied heat, term cross hatching." and then spirits of turpentine, to get off Mr. Spencer, in his endeavour to obthe cement;, and to my satisfaction Itain a suitable compound, tried a variety found, that the voltaic copper had com- of experiments upon different

compopletely combined itself with the sheet on sitions formed of wax, resins, varnishes which it was deposited.”

and earth, and also with metallic oxides. One other quotation from Mr. Spen- At last he obtained one which for all cer's paper, read before the Liverpool his purposes seemed to be admirably Polytechnic Society, we must be al suited; it was formed of virgin wax, lowed to extract, as it will be found resin, and carbonate of lead. With this to contain a valuable hint to those who cement, two plates, five inches by seven, may attempt a certain class of the ex- were covered, and portions of maps enperiments we shall have occasion here. 'graven on them. This being done, they

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were dipped in dilute nitric acid, a pro- thickness of a shilling. I then pro

cess found in other instances so bene- ceeded to get the deposition off. In Eficial, and then introduced into the vol- this I experienced some difficulty, but taic

arrangement. The intention was ultimately succeeded. On examination, to have formed metallic casts fit for with a magnifying glass, I found every printing, more especially with the view line was as perfect as the coin from of presenting them and the printed which it was taken. I was then insheets to the British Association. When duced to use the same piece again, and the process had been continued suffici- let it remain a much longer time in ently long, heat was applied to the plate action, that I might have a thicker and to remove the cement : but to the more substantial mould. I accordingly amazement of the experimenter the volput it again in action, and let it remain taic copper pealed off with the etching until it had acquired a much thicker coatground. The cause of this it was at ing of the metallic deposition ; but when first difficult to determine; but on clean- I attempted to remove it from the medal, ing the plate, a delicate tracing of lead I found I was unable. It had apparently was found on the line drawn on the completely adhered to it. cement previous to the immersion in “I had often practised, with some the dilute acid. “The cause of this degree of success, a method of prefailure, says Mr. Spencer, was at venting the oxidation of polished steel, once obvious ; the carbonate of lead I by slightly heating it until it would had used to compound the etching melt virgin wax; it was then wiped, ground, had been decomposed by the apparently completely off, but the pores dilute nitric acid, and the metallic lead, of the metal became impregnated with thus set free, had deposited itself on the the wax- -I thought of this method, and exposed portions of the copper plates, applied it to a copper coin. preventing the voltaic copper from che- "I first heated the piece, applied wax, mically combining with the sheet cop- and then wiped it so completely off, that per. I was now obliged with regret the sharpness of the coin was not at all to give up this compound; although, interfered with. I proceeded as before, under other circumstances, I have no and deposited a thick coating of copper doubt it may be rendered available.” on its surface. After the lapse of a few

The cement which was ultimately days, when I wished to take it off, adopted by Mr. Spencer, was formed I applied the heat of a spirit lamp to of bees' wax, common whiting, resin, the back, when a sharp crackling noise a small portion of gum, and plaster of took place; and I had the satisfaction of Paris. This compound, he speaks of as seeing that the coin was completely answering the purpose tolerably, though / loosened. In short, I had a most comhe anticipates a better may be found. plete and perfect copper mould of a half

We cannot close this examination of penny. the labours of Mr. Spencer, without an “I have since taken some impres. allusion to the results of his experiments sions from the mould thus formed; and in an attempt to obtain impressions in by adopting the above method with the cameo and intaglio, although we intend wax, I get them out with the greatest in another number to explain the method in which the various experiments "I was now of opinion that this latter may be performed. From what has method might be applied to engraving, been already stated, the reader must be much better than the method described aware that no metallic deposition can be in the first portion of this paper. Being obtained by the action of voltaic elec- aware that copper in a voltaic circuit tricity, without a metallic body, or we deposited itself on lead with as much might more properly say a metallic sur- rapidity as on copper, I took a silver face, as a nucleus. Bearing this fact coin, and put it between two pieces of in mind, the following observations, by clean sheet lead, and placed them under the discoverer of the process, must be a common screw press. From the softread with interest.

ness of the lead, I had a complete and "I placed a very prominent copper sharp mould of both sides of the coin. medal in a voltaic circuit (as already I then took a piece of copper wire, soldescribed) and deposited a surface of dered the lead to one end, and a piece copper on one of its sides to about the of zinc to the other, and put them into

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192

Gud's chief GIFT-SALVATIONWEAKNESS OF HUMAN RESOLUTIONS.

on its

the same voltaic arrangement I have on the unchangeable interest he had in already described. I did not, in this his Father's love; and on the Father instance, wax the mould, as I felt as- delivering him up to an execrable death sured that the deposited copper would for mere sinners, we cease to wonder easily separate from the lead, by the that, with him, he freely bestows all spiapplication of heat, from the different ritual blessings, without any regard to expansibility of the two metals.

worthiness in them on whom they are “ In this result, I was not disap- conferred. Because the gift of Christ pointed. When the heat of a spirit himself is the grand evidence of God's lamp was applied for a few seconds to love to sinners, incomparably greater the lead, the copper impression fell than that of authorizing the ungodly to easily off. So complete do I think this believe in Jesus, or than that of his givlatter portion of the subject, that I have ing heaven to saints.-Booth. no hesitation in asserting that fac-similes of any coin or medal, no matter of what

SALVATION. size, may be readily taken, and as sharp as the original. To further test the ca- substituted himself in the place of sin

Our Saviour, Jesus Christ, having pabilities of this method, I took a piece of lead plate, and stamped some letters ners, suffered in his own person the

punishment of sin, conformably to that rface to a depth sufficient to declaration, “ In the day that thou eatest print from when in relief. I deposited thereof, thou shalt surely die." He copper on it, and found it came easily off. "to of

came forth from among the dead in my experiments on this subject. As I testimony that the threatening of God stated at first, my object was to deposit the acceptance of his sacrifice, and that

was accomplished, and as a pledge of a metallic surface on a model of clay, by his obedience

unto death Divine jus, or other non-metallic body; as, other- tice was satisfied, the law honoured and wise, I imagined the application of this principle would be extremely limited. magnified; and that eternal life was

awarded to those for whom he died, I made many experiments to achieve whose sins he had borne in his own this result which I shall not detail, but body on the tree, 1 Peter ii

. 24. He content myself with describing that was quickened by the Spirit, by whom which was ultimately the most success- he was also justified, 1 Tim. iii. 16, from ful. “I

took two models of an ornament, every charge that could be alleged one made of clay, and the other of against him

as the surety of them whose plaster of Paris; soaked them for some therefore, of his people, which includes

iniquities he bore. The justification, time in linseed oil, took them out, and not only the pardon of their sins, but suffered them to dry, first getting the also their title to the eternal inheritance, oil clean off the surface. When dry, I gave them a thin coat of mastic var- fected in his resurrection. He wrought

was begun in his death, and was pernish. When the varnish was as nearly their justification by his death ; but its dry as possible, but not thoroughly so, efficacy depended on his resurrection. I sprinkled some bronze powder on that portion I wished to make a mould By his death he paid their debt, in his of. This powder is principally com

resurrection he received their acquit

tance. He rose to assure to them the posed of mercury and sulphur; I had however a complete metallic coating on

right to eternal life, fully to discover the surface of my model, by which I it, and to establish it in his own person,

for all those who are the members of was enabled to deposit a surface of cop- his body.-R. Haldane. per on it, by the voltaic method I have already described. I have also gilt the surface of a clay model with gold leaf, WEAKNESS OF HUMAN RESOLUTIONS. and have been successful in depositing To attempt to resist temptation, to the copper on its surface.” H. abandon our bad habits, and to control

our dominant passions, in our own unaided strength, is like attempting to

check by a spider's thread, the progress When we reflect on the personal dig- of a ship of the first rate borne along nity of Jesus Christ, as the Son of God; I before wind and tide.- Waugh.

GOD'S CHIEF GIFT.

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THE BEECH.

creepeth on the earth,” are placed under
his dominion. “Every herb bearing
seed, and every tree in the which is the
fruit of a tree yielding seed,” is given
him for meat, either directly or through
the medium of the cattle and feathered
fowl on which he is permitted to feed.
Nor are the treasures of the earth se-
cured from his grasp; to him the mine
yields her invaluable stores, and the
forests of the antediluvian world their
fossilized timber.
“All are for health, or food, or pleasure given,
And speak in various ways the bounteous hand

of Heaven,"
though the products of a single tree
would have sufficed to furnish him, not

only with the necessaries, but even the al с

luxuries of life. Witness that noble Beech (Fagus sylvatica.) a, catkin of male flowers. 6, male flower. c, female flower. d, ger- adorns their scenery, supplies the sim

tree the cocoa palm, which, while it e, capsule, or nut. NATURAL ORDER. Corylaceæ.

ple wants of the inhabitants of the LINNEAN ARRANGEMENT. Monccia Polyan- tropics; and is capable, as Strabo tells dria. Fagus Sylvatica.

us, of being applied to three hundred Barren Flowers in a roundish elongated catkin. and sixty different purposes. Calyx of one leaf divided into five or six segments. Corolla none. Filaments from five to twenty,

The Indian's nut alone hair-like, longer than the calyx. Anthers, round- Is clothing, food, and trencher, drink, and can, ish or oblong, two-lobed. Fertile Flowers. Calyx

Boat, cable, sail, and needle, all in one.” double ; the outer inferior, leathery, externally covered with simple prickles, divided into four, five,

Hence he derives timber for the walls, or six deep segments, and containing two or three and thatch for the roof of his hut, fuel inner calyxes or flowers,

each superior of one leaf, for his fire, and weapons for defence ; with five or six deep segments, internally woolly. Corolla none.

Germens, two or three below the the exhilarating spirit, the luscious suinner calyx, egg shaped, three or six celled with rudiments of two seeds in each. Styles three.

gar, the cooling milk, and the enlightStigmas undivided, permanent. Nuts two or three, ening oil: in a word, nutriment, beveegg shaped, more or less angular, attached to the

rage, and clothing. 6. With lavish base of the outer calyx, and crowned by the upper. A large tree with snooth bark and spreading kindness,” this gift of God is placed branches. Leaves, egg shaped, indistinctly ser- in every soil and variety of situation rate. Flowers in April and May.

within those regions it so greatly benefits. -The beech delights the glade, With boughs extended and a rounder shade.”

In the fertile valley, on the arid plain,

PRIOR. waving in tufted groves, or beetling the The beech-of oily nuts prolific.”—COWPER. craggy precipice, beside the rippling.

"Man wants but little here below;" rill, or on the coral reef, washed by food and water, raiment for his body, the spray of ocean,-in equal luxuriance and shelter from the inclemencies of the its taper column and plumy foliage afweather ; such are all his necessities, ford a pillared shade impervious to the and if these alone were supplied, he vertical" sun. But shall we envy the would have no cause to murmur. Yet enervated inhabitant of the torrid zone with what benevolent bounty has the his inestimable tree? Is the goodness Lord, whose “tender mercies are over of God limited to one particular clime, all his works,” provided not only for or confined to the natives of a single his wants, but for his pleasures, and land ? Through the whole earth his caused the means by which the cravings bounty shines ;" and the productions of nature are satisfied to gratify the eye, of every country attest his unwearied the taste, the fancy, the love for variety, beneficence and never-failing care, though and all the other dispositions of the too often disregarded and unacknowmind, by which this favoured object ledged by those whom he thus benefits. of creation is distinguished from the Hundreds doubtless can recount the vabrutes that perish. “The beasts of the ried products of the cocoa-nut tree, and field, the fowls of the air, and what- enumerate the many purposes to which soever passeth through the paths of the they can be applied, who are ignorant sea," with “every creeping thing that I that among the forests of Europe is to

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