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10. Having thus determined an epotha in the past events on the earth, chaacterized by a certain state in which it ust have been ; continuing to follow the dictates of facts, and the progress of our natural knowledge, I ascend to a time, defined in §§ 30 and 31, when nothing of what we now observe on our globe, 'namely, the mineral strata, composing the whole known mass of our continents, the sea and our atmosphere, could have been produced, because liquidity, without which no chemical effect could take place, (and consequently, no precipitation of the substances of our strata, nor any formation of elastic fluids) did not yet exist. The epocha, therefore, when all those effects began, is particularly characterised by the production of liqui'dity on our globe. But what new cause was required, for that new effect 2 11. Pursuing this analysis, I explain, § 34, in what liquidity consists: it is produced, without exception, at every temperature, by the union of the elements of the liquified substance, with a certain quantity of fire; or of the fluid, which, when uncombined, produces heat, (an effect measured by our thermometers,) but loses this faculty when combined with other substances, in which state it is called latent. Therefore, in § 35, I thus more distinctly determined the epocha to which we are to ascend, as the beginning of all the operations of which we see the effects on our globe: “when a sufficient quantity of fire was united with the substance which, when liquified, eonstitutes water, and in that state chemically combines with a great number of elements which they help each other to dissolve.” 12. We now arrive at the point that directly relates to Mr. Pilgrim's attack; which point is introduced in the above letter, by the following question: “How was fire produced " This question I then follow from the knowledge acquired in experimental philosophy; and in studying my deductions from it, Mr. Pilgrim
would find a subject of reflection, which
it does not appear he has ever considered. Fire is a compound fluid, and into its composition enters light, a substance which possesses chemical affinities, and indeed is the essential ingredient contributing to all chemical processes. Without light, in combination with another ingredient, no fire exists; and without fire, there exists no liquidity. ontinuing this analysis, I arrive at the $onclusion expressed in § 42, of
the same letter: “Nothing of all that we see on our globe could begin to be operated, previous to the introduction of a certain quantity of light into the whole mass of elements, till then incapable of cheinical action on each other. Therefore the beginning of all the geological phenomena that we know, takes its date from this union.” 13. This last conclusion referring to the whole of what I had before proved, it is evident that the moment of the first production of liquidity on our globe, must have been that of the commencement of all the operations impressed on it, which have been the object of geological researches; which operations continued without interruption, till the birth of our present continents. Had Mr. Pilgrim been acquainted with all which here I have only sketched, would he not have judged, that the only way of attacking me fairly, had been to meet me on that ground, and contradict either the fac's or the conclusions? 14. His next objection is expressed in the following words. “Provided we admit Mr. De Luc's opinion, it must evidently appear, that this planet, called earth, must have existed many ages prior to the creation of the sun ; a supposition that will not be entertained by any person of coionion understanding; and moreover, we are to conclude, that all the fixed stars are but in a juvenile state, compared with the age of the globe we inhabit; an idea that must be equally exploded by every person who has the least acquaintance with astronomy.” This must appear plausible to those who, like Mr. Pilgrim, are not acquainted with my works, and in particular with the Letters to Prof. Blumenbach, above quoted; but had he read only these letters, he could not have expressed himself in that manner. I shall repeat here briefly what he would have found there. 15. This sublime preamble, In the begunning God created the heaven and the earth, evidently comprises the stars, the sun, and other celestial bodies, as well as the earth. They had received their projectile motions, and they influenced on each other by gravity, which in particular occasioned the revolution of the planets round the sun; and their liquidity to a certain depth, with their notion on their axis, had given then the form which they actually possess. But were the sun and stars then luminous? If Mr. Pilgrim had known, or attentively read my works, to which I have referred, 2 E 2
he might have found first, that I am more acquainted with the physical part of astronomy than he appears himself to be; then he would have seen the results of experitments and observations which prove, that in order to enable bodies in themselves capable of phosphorcsectice, actually to omit light, there is required some previous in:erior chemical process, to de compose their moleculae, and disengage the light which has entered them as an ingredient. A few examples, which I purpose giving in your next, will be sufficient to evince this proposition.
Windsor. J. A. DE LUc. —---To the Editor of the Monthly Magazine. SIR,
HE following paragrap!, is literały copied from a provincial paper of
this month. It desorves to known beyond the limits of the co, colation of the paper; and if you think i' and the few remaiks annoxed, will no,' ' orace a corner of your valuable repository, they are at your service.
“A singular circumstance took place about a week ago in the neighbourhood of Penrith. A farmer, who had a ways expressed a great aversion to optizing or christening, had a child which died ; and in consequence of his predilection that none of his children should ever undergo the ceremony, the parishioners efused it burial, and application was made at , where a grave was prepared; but, previous to the time of interment, the circumstance came to the knowledge of the worthy vicar, who ordered the grave to be filled up again. When the child was brought to the town, they were much disappointed at what had taken place; and after waiting a length of time to no purpose, were necessitated to return home, and seek out for some other place of burial.”
The worthy, worthy, worthy vicar ! A poor innocent child is refused the ritcs and right of sepulture, notwithstanding a grave had been prepared for it, must rot on the surface of the earth, be worried by dogs, or devoured by the crows! Is this christianity ? is this the established religion of a civilized people? From what I have read of the humanity of the Hot. tentots, I think such a circumstance could never have taken place amongst them. Tell it not in Westmorland, nor publish it in the streets of Kendal, iest the Philistines, the infidels, the heathen, the Turk, hear it and rejoice.
Lancaster, + Dec. 1813. D. B. P. EccLESTON.
Mr. Eccleston on Modern Clerical Superstition. [April 1,
To the Editor of the Monthly Magazine, SIR, R. O. GREGoRY has accused me with making “the resistance, or, as Dr. !otton terms it, “efficacious force of the pier,’ to depend in a great measure upon the weight of the arch itsels;” but did not this occur from negligence, and “looking about” him? for surely, had he looked before ilim he must have “discerned” the difference between the two expressions so closely following each other; the first denoting Dr. Hutton's force of the pier, which does not depend in any measure upon the weight of the arch; and the second denoting what I have termed “the sun, of the r sistance of the pier,” and oth “depend in a great measure upon he weight of the arch itsels;” for LGXA the measure of what that dependance (4 being here put for “area of semiarch”), and is the proper resistance to what Dr. Hutton terms “the efficacious force of the arch to overset the pier, or turn it about the point G,” when his efficacious force of the pier, as there expressed, is the proper resistance to the esłotive force of the arch.
This distinction Dr. Ijutton was not, and Dr Gregory does not now seem to be, aware of; othe, wise he would not inculcate the doctrine he does in his concluding paragraph, for there he tells me, I mus' be convinced “ that the matter, which by its pressure upon a pier tends. to overset it, does not by means of the same pressure prevent it from being overturned.” All this I grant, provided he shews me that matter by its pressure upon a pier doth tend to overset it, but not otherwise; for what I contend for is, that matter by its pressure upon a pier does tend to prevent its being overturned; although the same matter by its pressure
against the pier, will tend to overset it. By what can be collected from the mode of argument made use of in this attack, does it not appear to “a discerning public,” as better calculated to intimidate me from writing upon the subject than to confute what I have already written ? and is it not probable he sancies that by degrading my abilities he can dissuade the young bridge-builder from relying upon them, and by this means increase the demand for Dr. Hutton's remodelled work, which he informs us is at length published But if those are his ideas, he is mistaken, as I have already received letters of thanks, for what has been published of mine in this Magazine; having in the number for May, 1812, not only .
only shewn that the Emersonian theory of arches, as Dr. Hutton has explained it, in his “Principles of Bridges,” is not a theory adapted to practical purposes: but one is there given that can be so adapted, and that without any fluxionary
rocess, but by common arithmetic only. 2. y
See also another letter of mine in the same publication for October, 1842, where I have added a second step to Mr. Ware's construction, in order to perfect what he fancied he had completed before; which was to equilibrate an arch by geometrical construction, and had a third step been added to it, the height of the Emersonian vertical would be obtained. This construction is not new, it being no other than an application of the Pythagorean Problem, or 47th of Euclid; so well known to carpenters and masons, partieularly the former, as it is by its means he finds the length of his rafter, after half the breadth of the building and the height of the roof are given; but for our purpose it is sufficient to observe, that by a proper application of it, every thing necessary, both for the equilibration of arches, and also their comparative and relative strength, may be found, and a knowledge of the latter is of more utility to the practical builder than the former; as an arch, when strictly in equilibrio, according to the terms of the theory, will not admit of the smallest ex
traneous weight being placed upon any .
part of it, without destroying that equilibrium, but when attached to matter, acquires, what is termed, strength. And it is on this the stability of arches depends; hence it is obvious, a knowledge of the quantum of that strength is a desideratum in the science, not hitherto noticed by any of the mathematicians who have treated on this subject; at least not to my knowledge.' It may be objected, that nothing upon this subject is noticed in my second letter, and this I admit; neither is there here any other than hints, but such hints as cannot injure, yet may stimulate to farther enquiry; and is all I can afford in this place, whatever I may do hereafter. But even grant that nothing more is done than what I have already written, and is published in the Monthly Magazine; it is not very probable the young artist will refer to Dr. Hutton's fluxionary process for instruction in the theory of arches, when it may with more ease be obtained, by referring to a few letters in this publication, or even to his carpenter. Jhen in respect to piers, if that subject is
not sufficiently explained in my last, I trust it will in this; for here I shall have the assistance of Dr. Gregory himself, the work hefore alluded to being no other than his “Treatise of Mechanics,” For article 208, vol. 1, of this work, not only contains cnough to prove the truth of what 1 before gave as Iny opinion, but also sufficient matter for correction and improvement, of which it stands in much need. What I shall first notice in this article, is an equation intended to express the force of an arch, and the resistance of a pier, when supposed to turn on a centre of rotation: the principles that this equation is deduced from, being those of mechanics; but the place and angle of abutment, to which it is applied, have no claim or affinity to that science; and that this is a fact will appear evident, evea from the directions given to find this place and angle. The rule is as follows: “Draw from the middle of the key voussoir, a tangent to the intrados, and produce it till it again meet the middle of another voussoir.” This point, or middle of this last voussoir, is to be considered as the place of abutment, and a line from the centre of curvature through that point, shew the angle this abutment forms with the vertical; the curve from its vertex to this point is all that is to be taken as the semi-arch, and the remaining part is to be considered as part of the pier, and to act with it in resisting the force of the arch. Hence it appears, that the place of abutment is to be governed by the length of the voussoirs, without any reference to the direction of the pressures; for it is evident, that their length determines the extent of this tangent line. To shew what will result from adopting this rule, an example or two will be sufficient; therefore suppose a line drawn from N to V, on the figure in my last letter, this line will intersect the curve at 33° 15' distance from the vertex, which, if taken as the semi-arch, the length of the voussoirs to admit this line, being drawif on their face, must be upwards of four feet, which is more than necessary (when stability only is required) in an arch of 51.25 feet radius; for the length of those in the celebrated arch over the Tāff, in Glamorganshire, where the radius is 87°5, is only 33 inches, and in respect to stability there can be no doubt, for that arch has been erected upwards of 60 years, and is now perfect. Then as the length of those voussoirs is sufficient, and the comparative strength
strength of arches is as the squares of the voussoir at the vertex, or depth of the arch at that point, when compared with radius of curvature to that point, the langth of the voussoir for that purpose, only in the first arch, need be no more than 25% inches. For as 87.5 : 51-25 :: 33* : 25.25°. But then the extent of this line, and consequently the place of abutment, will be at 23 degrees from the Vertex. But if a line after this manner was produced on the face of the voussoirs in the last arch, it would extend only to 20° 10’, and then there would be 33 degrees to be attached to the abutment, and to act as part of it, for the whole semi-arch is 53° 10'; and farther, if a vertical line was let fall from this place of abutment, it would be distant from the vertical axis only 30 feet, and from the face of the real abutment 40 feet, the semi-span being 70 feet. Such are the results that would ensue from adopting this rule, but it requires no farther comments, as it puts an end to our controversy. I shall now return to this equation, and here it is to be observed that the vertical pressure N m, and the horizontal pressure ma, which hy me were considered separate, are here considered as combined ih one; in the direction of Na. Then v37703 (N m2) + 16-40° (m a”) = 41.1756 the other pressure, or they are rather lines, in the direction and proportionate to the pressures. The vertical pressure is always equal to the weight or area of the semi-arch, which is here =809, and then the horizontal pressure
r=8557, the initial pressure. This last pressure, acting in the direction of the line N a continued, acts against another line or lever not represented on the figure, but supposed to be produced from G, the fulcrum or centre of rotation, on which the pier is supposed to turn to the line Na, and at right angles to it, which short line or Jever shall be denoted by G h, and whose length, upon investigation, is found to be 1.7863, which multiplied by 8557, the initial pressure, is = 1528:52, the effective force of the arch to overset the pier; then the weight of the pier, represented by its area, acting at E, as one end of the bended lever EGh, being multiplicd by the distance from E to G, will determine and shew the resistance of that pier; hence one whose thickness is 6:912, is
Title of King of France.
[April 1, sufficient in this case. For 6'912 (GL) ×64, (EF) ×3-456, (EG) = 1528.82, the resistance of the pier to the effective force of the arch, and nearly the same as that force. This is the result when the vertical and horizontal pressures are considered as combined in one, or Dr. Gregory’s method; next for that when they are considered separate, or the method which I have adopted.
Now ma is substituted for MA, Dr. Hutton's force of the arch will be express
ed by *x La-7120°33, and to ilt produce a resistance equal to this force will require a pier 14,917 feet in thickness, for 14.917x64x7-485-7120-63, nearly the same; but this is in consequence of no notice being taken of the vertical pressure of the arch, which counteracts the horizontal as before. Therefore I added it to the resistance of the pier, taking the thickness to be as in the first A x N in 71.20:33–G Lx EFX E. G+L GXA, or 1528.82 + 5591-808 = 7120.628, Dr. Hutton's force of the pier; but this equation might have been differently and m a x A N m X La—L GXA, or 7 120-33–5591.808– 1528,522, the resistance of the pier nearly as before. Here we have the results from three different methods of investigation, one of which is conformable to Dr. Gregory's theory, all agreeing with each other, but differing with Dr. Hutton's; which in opposition to me the former now supports. JAMES PARRY, Bridge-builder. Cardiff Feb. 1, 1814. ---For the Monthly Magazine. On the or iGIN of the TITLE of KING of FRANCE, assumed by the KINGs of ENGLAN D. MANUSCRIPT history of the ancient disputes between the sovereigns of England and France has lately been brought forward in Paris. It was written in 1572 by John Renard, a person unknown to bibliographers. In this work we are told that Edward the Third of England, to induce the Flemings to assist him in his war against Philip of Valois, engaged to put into their hands, Lille, Douay, and Bethune, taken from them by France. To this " offer the Flemings answered, that by, towaty they were restricted from making war against the king of France, under the penalty of forfeiting two millions of flo, rimsa
- in case, and then it was
more elegantly expressed by
rins, besides falling under the heavy censures of the church. Anxious however to accede to Edward's Proposal, the Flemings, after mature deliberation, hit upon an expedient by which their honour and their advantage could be reconciled. They counselled Edward to claim the throne of France, to quarter the arms of that country with those of England, and openly to designate himself *ing of France. In that case, said the wily Flemings, we can conscientiously acknowledge you as sovereign of the towns in question; we can bonestly accept then as a gift at your hands; and we can lawfully and securely carry aims against the usurper Philip of valos. The title of King of France was always afterwards employed oy dward, even when writing to Phil., himself; and it is not a little curions, that the relinquishment of that title, offensive and insulting to a great and independant nation, pertinaciously refused to the most powerful legitimate sovereigns of France, was at a late Period, without difficulty, acceded by Britain to a person not unfrequently styled, in that very country, a lawless usurper. --- X. To the Editor of the Monthly Magazine.
R; CIR Thomas Herbert relates in his Memoirs of the two last years of King Charles I. that the king, on the morning of his execution, commanded him to give “the Duke of York his large *ing sun-dial of silver, a jewel his maJesty much valued; it was invented and made by Mr. Delamaine, an able mathematician, who projected it, and in a little printed book shewed its excellent use in resolving many questions in arithmetic, and other rare operations to be wrought by it in the mathematics.” Permit me to ask your readers for any information they possess respecting the existence of this ring-dial, and particularly if Mr. Delamaine's “little printed book” is in existence, its size, number of pages, date, and by whom published. March 1, 1814. M. E. P. S. Herbert gives the best account that I have seen, of the mode and place of burial of Charles. He was entrusted by the parliament with the funeral. The body lately found at Windsor is undoubtedly the king's. -For- To the Editor of the Ionthly Magazine. * SIR, N the library of the London Institute stands a quarto volume, entitled, “A Collection and Abridgement of celebrated - - &
Criminal Trials in Scotland, from 1536 to 1784, with historic and critical remarks, by Hugo Arnot, esq. advocate : Edinburgh, 1785.” At page 324 is the soilowing case. Thomas Aikenhead appears to have been about twenty years of age ; his father, who had been a surgeon at Edinburgh, was dead. Sir James Stewart, his majesty's advocate, by special order of the privy council, served him with a criminal indictment before the court of Justiciary for blasphemy.—Records of Justiciary, Dec. 23, 1696. The libel sets forth, that blasphemy against God, or any of the persons of the blessed Trinity, or against the holy scriptures, or our holy religion, is a crime of the highest nature, and severely punishable by the laws of God, by those of this and every wo.' governed realin, and particularly by act of parliament, 1696. Sec. v. c. 2, 11 [silliam, That, notwithstanding, the prisoner had repeatedly maintained in conversation, that theology was a rhapsody of ill-invented nonsense, patched up partly of the moral doctrines of philosophy, and partly of poetical fictions and extravagant chimeras. That he ridiculed the holy scriptures, calling the Old Testament Ezra's fables, in profane allusion to Esop's fables. That he railed on Christ, saying he had learned magic in Egypt, which enabled him to perform those pranks which were called miracles. That he called the New Testament the history of the impostor Christ. That he said Moses was the better artist, and the better politician ; and he preferred even Mahomet to Christ. That the holy scriptures were stuffed with such madness, nonsense, and contradictions, that he admired the stupidity of the world in being so long deluded by them. That he rejected the mystery of the Triinity as unworthy of refutation, and scoffed at the incarnation of Christ, saying that a theanthropos, or God-man, was as great a contradiction as a hircocervus, or goat stag, or that a square was a round. That he laughed at the doctrime of redemption: and said the notion of a spirit was a contradiction. That he cursed Christ, and argued against the being of God; maintaining that God, the world, and nature, are all one thing, and that the world existed from all etermity. That he said the inventors of the scripture-doctrines would all he damned if there was such a thing as rewards or punishments after this life; and that Christianity itself would soon he extirpated.