Verse 25. "But the word of the Lord" - The doctrine delivered by God concerning Christ endureth for ever, having, at all times and in all seasons, the same excellence and the same efficacy.
"And this is the word" - to pnma, What is spoken, by the Gospel preached unto you. "This is a quotation from Isa. xl. 6-8, where the preaching of the Gospel is foretold; and recommended from the consideration that every thing which is merely human, and, among the rest, the noblest races of mankind, with all their glory and grandeur, their honour, riches, beauty, strength, and eloquence, as also the arts which men have invented, and the works they have executed, shall decay as the flowers of the field. But the Gospel, called by the prophet the word of the Lord, shall be preached while the world standeth." - Macknight. All human schemes of salvation, and plans for the melioration of the moral state of man, shall come to naught; and the doctrine of Christ crucified, though a stumbling block to the Jews, and foolishness to the Gentiles, shall be alone the power of God for salvation to every soul that believeth.
As the apostle, on ver. 7, mentions gold, and gold chemically examined and tried; and as this figure frequently occurs in the sacred writings; I think it necessary to say something here of the nature and properties of that metal.
Gold is defined by chemists to be the most perfect, the most ductile, the most tenacious, and the most unchangeable of all metals. Its specific gravity is about 19?3. A cubic foot of pure gold, cast and not hammered, weighs 1348lbs. In its native state, without mixture, it is yellow, and has no perceptible smell nor taste. When exposed to the action of the fire it becomes red hot before it melts, but in melting suffers no alteration; but if a strong heat be applied while in fusion, it becomes of a beautiful green colour. The continual action of any furnace, howsoever long applied, has no effect on any of its properties. It has been kept in a state of fusion for several months, in the furnace of a glass house, without suffering the smallest change. The electric and galvanic fluids inflame and convert it into a purple oxide, which is volatilized in the form of smoke. In the focus of a very powerful burning glass it becomes volatilized, and partially vitrified; so that we may say with the apostle, that, though gold is tried by the fire - abides the action of all culinary fires, howsoever applied, yet it perisheth by the celestial fire and the solar influence; the rays of the sun collected in the focus of a powerful burning glass, and the application of the electric fluid, destroy its colour, and alter and impair all its properties.
This is but a late discovery; and previously to it a philosopher would have ridiculed St. Peter for saying, gold that perisheth.
Gold is so very tenacious that a piece of it drawn into wire, one-tenth of an inch in diameter, will sustain a weight of 500lbs. without breaking.
One grain of gold may be so extended, by its great malleability, as to be easily divided into two millions of parts; and a cubic inch of gold into nine thousand, five hundred and twenty-three millions, eight hundred and nine thousand, five hundred and twenty-three parts; each of which may be distinctly seen by the naked eye! A grain and a half of gold may be beaten into leaves of one inch square, which, if intersected by parallel lines, drawn at right angles to each other, and distant only the 100th part of an inch; will produce twenty-five millions of little squares, each of which may be distinctly seen without the help of glasses! The surface of any given quantity of gold, according to Mr. Magellan, may be extended by the hammer 159, 092 times! Eighty books, or two thousand leaves, of what is called leaf gold, each leaf measuring 3 3 inches square, viz. each leaf containing 10 89 square inches, weigh less than 384 grains; each book, therefore, or twenty-five leaves, is equal to 272 25 inches, and weighs about 4 8 grains; so that each grain of gold will produce 56 718, or nearly fifty-seven square inches! The thickness of the metal thus extended appears to be no more than the one 282 020th of an inch! One pound, or sixteen ounces of gold, would be sufficient to gild a silver wire, sufficient in length to encompass the whole terraqueous globe, or to extend 25, 000 miles! Notwithstanding this extreme degree of tenuity, or thinness, which some carry much higher, no pore can be discerned in it by the strongest magnifying powers; nor is it pervious to the particles of light, nor can the most subtile fluids pass through it. Its ductility has never yet been carried to the uttermost pitch, and to human art and ingenuity is probably unlimited.
Sulphur, in the state of a sulphuret, dissolves it; tin and lead greatly impair its tenacity; and zinc hardens and renders it very brittle. Copper heightens its colour, and renders it harder, without greatly impairing its ductility. It readily unites with iron, which it hardens in a remarkable manner.
The oxigenated muriatic acid, and the nitro-muriatic acid, dissolve gold. In this state it is capable of being applied with great success to the gilding of steel. The process is very simple, and is instantaneously performed, viz.:-
To a solution of gold in the nitro-muriatic acid add about twice the quantity of sulphuric ether. In order to gild either iron or steel, let the metal be well polished, the higher the better: the ether which has taken up the gold may be applied by a camel hair pencil, or small brush; the ether then evaporates, and the gold becomes strongly attached to the surface of the metal. I have seen lancets, penknives, &c., gilded in a moment, by being dipped in this solution. In this manner all kinds of figures, letters, mottoes, &c., may be delineated on steel, by employing a pen or fine brush.
The nitro-muriatic acid, formerly called aqua regia, is formed by adding muriatic acid, vulgarly spirit of salt, to the nitric acid, formerly aqua fortis.
Two parts of the muriatic acid to one of the nitric constitute this solvent of gold and platina, which is called the nitro-muriatic acid.
Gold was considered the heaviest of all metals till the year 1748, when the knowledge of platina was brought to Europe by Don Antonio Ulloa: this, if it be a real metal, is the hardest and weightiest of all others. The specific gravity of gold is, as we have seen, 19?3; that of platina is from 20?6 to 23: but gold will ever be the most valuable of all metals, not merely from its scarcity, but from its beautiful colour and great ductility, by which it is applicable to so many uses, and its power of preserving its hue and polish without suffering the least tarnish or oxidation from the action of the air.