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well as the one directly before the eye,) all perpendicular to the horizon or reflecting plane. The eye continuing fixed, with a pen or pencil trace the objects upon the pane of glass as they there appear to the eye, and thus you will have a true picture or perspective of the objects and their reflections. And as each object and its reflection are in the same plane, and perpendicular to the horizon, the intersections of their respective vertical planes, with the plane of the picture, will be also similar, and perpendicular to the horizon, whatever be the horizontal bearings of the objects to the eye. If you change the place of the eye there will certainly be a new picture, but whilst the objects continue perpendicular to the reflecting surface, or the horizon, (as in a piece of still water,) the representations of the reflections, as well as those of the objects, will be perpendicular to the horizon, whatever be the situation of the eye. And this Mr. Ross will instantly perceive if he is not wilfully blind. The objects and the reflecting plane remaining the same, Mr. Ross will find that in whatever direction he moves his eye, the reflections, like the objects, will be perpendicular to the horizon, both in nature and in the picture. If the objects incline to the horizon, or reflecting surface, the reflections will also incline to the horizon or reflecting surface, and be subject to the same laws of perspective as their originals. For every point of the object will have its reflection in the same vertical plane, owing to the angle of incidence and reflection being in the same plane, and perpendicular to the reflecting surface. Hence it is manifest that reflections observe the same laws, both in nature and in the picture, as the objects that produce them, and that the vanishing point of reflections, like all lines in perspective, vanish in infinity. If the objects are not parallel to the perspective plane, they have a vanishing point in the picture, and so have their reflections; and the latter, if truly delineated on that plane, will tend to the accidental point, like all other real objects in nature when referred to the perspective plane. As Mr. Ross appears in his last two letters to suspect the truth of his own hypothesis, I shall feel gratified if the above remarks afford him any assistance in ar
riving to a more accurate and scientific
conclusion, on a subject so interesting to the picturesque artist. T. SQUIRE. £pping, May 10, 1814.
To the Editor of the Monthly Magazine.
st R, Th; enclosed are my annual results of the weather for the past year. Should you deem them worthy a place in your Magazine, you will oblige me by inserting them therein. THOMAS HANson.
Meteorological Results of the Pressure and Temperature, deduced from Diurmal Observations made at Munchester in the Year 1813; by Mr. Thomas Hansom, surgeon. Lat. 53°.25' North, Long. 2°. 10' West of London. January.—The commencement of this period was mild, cloudy, and humid, the wind being for the most part south; rain fell in six instances, at intervals, to the 13th ; when there was a slight fall of snow for the first time;—an easterly wind, diminished temperature, and dry atmosphere, were now the leading occurrences to the end;—the minimum temperature of 22° was on the night of the 25th. February was decidedly a warm month, as it was attended for the most part with a south and south-west wind, but which blew very strong: on five days hurricanes occurred ; they blew chiefly from the south-west quarter, and were attended with frequent showers of rain.— On the 13th there was a faint lunar halo; and on the 23d hoar frost. March.-The first ten days were mild and warm, with a few showers of rain; but the temperature experienced a sudden depression on the 12th ; this arose from a change of wind from west to north, but its continuance in that quarter was of short duration : for the monthly maximum was on the 18th, being an augmentation of 31°.—Rain, with slight showers of snow, closed the mouth.-Wind south and west on nineteen days, its strength never reached a hurricane,— Upon the whole the weather was favourable to vegetation. April was ushered in with a low pressure and temperature; the latter shewed its monthly minimum on the 4th; previous to which there were several showers of snow, hail, and peals of thunder; which were succeeded by a quick augmentation of temperature, as well as a gradual one of pressure.—On the 10th the weather became so serene, warm, and brilliant, that the thermometer indicated a summer's heat, being as high as 60°, which was an increase since the 4th of 37°;—vegetation of course made a rapid progress, but being too early a check might might be expected; accordingly the last ten days were marked with frequent showers of snow and ha'i, and boisterous north and north east winds, which did great damage to vegetation, particularly to tender buds, and foliage in exposed situations. Blossoins of fruit-trees, &c. were never known to be more promising, but the severity of temperature, and hail storms, but particularly of the strong east winds, almost Stripped them of their beauty. May.—Although there was a gradual jucrease of heat, from the commencement of this period, yet the prevailing easterly winds had not ceased to be destructive till about the seven h, when the weather became more mild, and nature seemed once more eager to repair the injury done to trees and vegetation.— Rain about this time was much wanted, as the fall in the two preceding months had scarcely exceeded two inches in
506 Mr. Hanson's Meteorological Journal for 1813. [July *
depth —From the seventh to the twenty
sixth, rain fell daily, with the exception of the twelfth, sometimes in very heavy and long continued showers, and in four instances with thunder and lightning. On the 24th, a hail shower:—this period was generally favourable to the produe. tions of the earth. June.—In two instances the diurnal temperature was lowered to 50°; the first was on the sixth, and was in consequence •f an easterly wind ; the latter was on the 19th, and which was immediately preceded by six days of almost incossant but gentle showers of rain. On the 13th, a shower of hail. This month wo.s frequently marked with brilliant days, which, with the rain, were very seasonable. July.—Was remarkable for much thunder and lightlying, interspersed with showers of rain, and in two instances hail.—On the 30th, aster a high but desuitory state of temperature, there was a sudden augmentation of $2°, being as high as 83°:—the monthly minimum of 44° occurred on the third, being a dif. ference of 39°. August.—The first twelve days of August were cloudy and rainy, which had the effect of fowering the temperature; for on the 24th, the minimum was as ow as 42°.—The force of evaporation obeys the vicissitudes of temperature; in the present instance, the monthly quantity is four-tenths of an inch less than the evaoration for July. Neither thunder, ightning, nor hail, occurred; and there were few changes of atmospherical pressure, but the two principal oncé commanded great ranges.
September.—The weather for the first fifteen days was very gloomy, cloudy and wet, with an unsettled state of temperature.—In ahout sixty hours, viz. from the 7th to the 10th, there was a loss of 27° ef temperature, when it became more settled; with a brilliant serene atmosphere and a high barometrical pressure, which continued to the end.
October–On the fourth, the temperature was at the monthly maximum, when rain feli very copiously; the temperature now continued to descend to
the 18th, when freezing was observed
the first time this season.—The heat soon after rose, and the weather to the end was fine and dry, with the exception of the two last days.-Prevailing winds, south-west, November.—The most prominent variation in this month was, the vibratory impulso given to the atmospherical pressure during the first half of the month; indeed a similar occurrence took place at the same time with the temperature. The weather upon the whole was mild for the season, as the temperature was very seldom under freezing.—ttain fell copiously from the 8th to the 18th.-No. hail was noticed, and there was only one appearance of snow. I)ecember —Was decidedly gloomy, cloudy, and rainy; but not so cold as is usually the case at this time of the year; except the few last days, the nightly state of temperature, (in consequence of a continuance of a gentle north wind): was lowered upon three instances, eight. degrees under fetzing. The annual barometrical pressure for the past year, is 29,900 inches; the maximum of 30,75 occurred twice, viz. on the 22d of January, and the 26th of Decenher.—The minimum of 28.24 inches, was on the 17th of October; the range of the two extremes of course will be 2,51 inches.—The greatestvariation in twentyfour hours for the whole year, was on the 14th of November, being 1,55 inches. The mean annual temperature is 48°,66, being half a degree more than the annual temperature of 1812; the maximum was on the 30th of July, and the minimum on the 26th of January; the difference of the two extremes, will make a range of 61°. Greatest variation in ... enty-four hours was 28°, which occurred on the 14th of April.—The mean temperature of the six summer months is 56°,28, and for winter 41° 04. The aunual fall of rain, snow, hails &c. is near 35 inches in depth; Mr. George Walker's account of rain, is two 4. inches
Sinches more, but the low situation of his
-oTo the Editor of the Monthly Magazine. SIR, T OBSERVE in your Magazine for February last, a letter signed I. M. in which the writer requests some information respecting an oid arched gateway at Dunbarton ; and I am glad to have it in my power to communicate a few particulars concerning it, which, though trifling, I hope may not be unacceptable to your correspondent. Having visited Dumbarton some years ago, when on a tour in the west of Scotland, the venerable gateway, or college bow, as it is called, attracted my notice; and from the best information that could be obtained, I understand it did not beloug to a college or seminary for the instruction of youth, but to a collegiate church, which formerly stood there. According to the peerage, and other authorities, this collegiate church was founded about the year 1450, by the Lady Isabella, Duchess of Albany and Countess of Lennox, the widow of Murdoch, Duke of Albany, who was beheaded at Stirling in 1425. It was dedicated to St. Patrick, the Apostle of Ireland. The chapter consisted of a provost and several prebendaries; and for the support of the establishment, various lands and churches were mortified by the illustrious foundress. Some of the provosts were inen of distinguished rank, eminent for their piety and learning, and who were promoted to the highest situations in the kingdom.
London, May 14, 1814. N. C. - ---so..To the Editor of the Monthly Magazine.
SIR, A” literary societies have been the means of enlarging the sphere of human knowledge in times past, so it is probable they will be the chief inst uinents of its diffusion in the ages to come, and of ushering in that desirable period when reason shall obtain the dominion over the grovelling passions and appetites of men, and intellectual light shall shed
its influence on very region of the globe.
ters of men on principles purely of a mora! and intellectual nature. To act otherwise would be bencath the dignity of those who profess to be guided by rational motives, and whose aims are directed to the improvement of the mind. In admitting candidates whose literary character and acquirements are not gemerally known, it might not be improper to require them to write an essay on any subject with which they are best acquainted, to be presented to the society; or to submit to the examination of a committee, either on some general subject, or on that particular department of science or art which they wish chiefly to cultivate. Siłould the result be unfavourable to the candidate, he might be directed as to the mode of prosecuting His etiquiries, and to the books it might be proper for him to peruse; and at the &od of a year, or other period, he inight again be examined with regard to the progress he has made, by which means the society would learn whether his adinission would encrease the mental vigour of the association. With regard to persons whose literary qualifications are generally known, every dignified and honourable means should be used to induce them to patronise the institution by becoming members, and contributing by timeir talents and influence to promote its leading views. Persons of known abiHity and lovers of science residing at a distance might also be respectfully requested to become honorary members, and to promote the object of the society by occasional communications. Although money be an useful article in all societies, yet I would deem it inexpedient, and unworthy of the dignity of a rational institotion, to solicit any individuals not otherwise qualified to become members, chiefly with a view of their contributing to the pecuniary interests of the association. Such persons would not only be a dead weight on the society, but by the undue influence they would have might tend to impede its progress, and prevent its chief design from being accomplished. Besides their literary acquirements, the moral qualifications of those who desire admission into the society ought not to be altogether overlooked. Knowledge is chiefly desirable in proportion as it is useful. if it does not lead its possessor to propriety of moral conduct, its utility, at least to hir, may be much questioned. There have been some men of genius (I
hope their number is small) who have.
thrown disgrace on science by their habitual indulgence in those immoral
courses which are the bane of society” and degrading to the human character" To count association with such, notwithstanding their literary genius, would not reflect much honour on any society. For in all rationai institutions the amelioration of the moral characters and dispositions of mankind ought to form as prominent an object as the illumination of their understandings. We lose one of the strongest arguments in favour of rational information when we behold its possessors, in their moral conduct, habitually degrading themselves to the level of the dregs of imankind. The next topic on which I shall offer a few remarks shall be, II. The subjects of discussion, and the mode of conducting it.—Every subject which has a to ndency to induce a habit of rational thinking, to elevate and ennoble the mind, and to present sublime and interesting objects of contemplation; every subject which tends to unfold the wise arrangements of nature, and the laws by which the economy of the universe is regulated; every subject which tends to promote the progress of science, the practice of the liberal and mechanical arts, and the moral improvement of mankind, might occasionally become topics of discussion in a society constituted on the principles to which I have already alieded. These subjects would embrace the prominent parts of natural history, geography, astronomy, experimental philosophy, chemistry, natural theology, ethics, education, arts and manufactures, domestic economy, and similar branches of knowledge. It would be expedient, for different reasons, to exclude minute discussions on politics and revealed religion, as they might lead to those jars and contentions which have unhappily taken place between politicians and divines. At the same time I would not consider certain general topics connected with religion and politics, such for example as the general principles of legislation, the causes of the wealth of nations; the nature of the Supreme Being, the immortality of the soul, and similar topics, as be. yond the province of a literary society; as . such subjects may be discussed in a philosophical manner, without interfering with those local and temporary disputes and peculiarities of opinion which subsist in the church or in the state." ' ' ' " In the discussion of subjects there are four different modes which might be occasionally used. The first mode to which I allude is that of public lectures. This is the most common, and perhaps *of
the best methods of explaining and illustrating any particular subject, more especially when experiments or diagrams are necessary to elucidate the doctrines delivered. A lecture delivered once every month, or oftener, as may be judged expedient, by a person qualified to unaertake the task, on some interesting subject of natural history, chemistry, or experimental philosophy, might be attended with a good effect. But as a considerable degree of general information, of judgment, of mental labour, and of talent for composition, are requisite in order to make a respectable appearance as a lecturer, the person or persons employed ought to have a suitable compensation for their trouble. In order to raise a sum for this purpose, persons not members of the society might be invited to attend on the condition of paying a small contribution; the members at the same time contributing a little, though in a smaller proportion. One special advantage attending this mode of instruction is, that a subject can be more fully, methoslically, and familiarly, explained and illustrated on this plan than in any other way. In order to excite attention and to stimulate the exercise of the rational faculty, an examination, of such of the auditors as chose to submit to it, on the different particulars detailed in the lecture, might take place either at the conclusion of the lecture or at some future hour; and at the same time an opportunity offered of stating any difficulties or objections which may have occurred to them in order to their solution. 2. The next mode which I have in view is, that of the most intelligent members composing essays and reading them to the society. This exercise, while it might be the means of occasionally communicating useful instruction to the society, would also have a good effect on the writers themselves, in exciting them to arrange their ideas in a regular train, and to express them with propriety, by which meåns they would gradually acquire the habit of accurate composition. It would also teach them candour in judging of the writings of others; for no one is fully sensible of the difficulty of writing with perspicuity and correctness till he himself has made the experiment. For the benefit of young writers it might be proper, in a candid and friendly manmer, to point out the grammatical blunders, improper phrases, erroneous statements, or other improprieties, which may be found in the essay; and the writer MonTHLY MAG. No. 256.
ought to consider such hints as so much new and useful information, by the help of which he may be enabled to render his future compositions more correct. Were any one disposed to despise such friendly hints I would despair of his future progress in knowledge; for to be convinced of our ignorance and mistakes is the first step to our future improvement. In order to make a respectable figure as writers of essays, particular attention should be given to the arts of grammar and composition; and exercises and instructions on these subjects might occasionally form a part of the business of the society. For as language is the medium by which we communicate our thoughts, we cannot do so with perspicuity and energy unless we pay some attention to the study of words and their various combinations. An essay embodying a number of good thoughts, if it abounds with errors of grammar, coarse and obsolete phrases, perplexed sentences, and confused arrangement, will always produce a very disagreeable effect. Such a composition would be unfit for public inspection, even although it should contain a number of original views and deductions. As some essays may occasionally be read of which the society may wish to have copies for future inspection, in order to save the trouble of the secretary transcribing them, it might be proper to recommend that cwery essay be written on paper of the same size, so that they might afterwards be bound in regular volumes, to be preserved as part of the records of the society. In this way the literary comamunications made to the society would be recorded in the hand-writing of their respective authors, free of those errors which might be occasioned in their tran
scription by another hand. 3. Another mythod of discussion might be by Forensic Disputations. In this case a question is proposed and stated, and op. posite sides of the question are supported by different speakers, the one affirming and the other denying, and producing reasons to support their respective opinions. This method hath its advantages and its disadvantages. Its disadvantages are, that persons, in their eagerness to support the side they have taken, are sometimes apt to contend more for victon ry than for truth; and, unless they watch over their tempers, are ready to fall into a spirit of altercation and ill-humour, and to throw out unhandsome epithets against their opponents. Many persons 3 U. too,