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INVENTION OF THE QUADRANT.
with the necessary accuracy, will not, perhaps, be so telescope P Q is fixed, of a good aperture and field, easy in practice as he would have it believed.
with the axis placed as above. The limb is to be gradui shall, therefore, here presume, from thy favour ated by diagonals, or parallel circles, to half degrees and shown me in England, in 1724, to communicate an in- half minutes, beginning from C, which are to be num. vention that, whether it answer the end or not, will be bered as whole ones. And if it be practicable to face allowed, I believe, to deserve thy regard. I have it wood with brass without warping, the wbole face should thus:
be so covered; if not, then along the outward edge of A young man, born in this country, Thomas Godfrey the limb a narrow strip of brass plate may be let into the by name, by trade a' glazier, who had no other education face of it, finely and equally indented on the edge, to than to learn to read and write, with a little common take a screw fitted to that toothing to be fixed on the arithmetic, having, in his apprenticeship with a very moving index at L, as your instruments are made that poor man of that trade, accidentally met with a mathe- count by revolutions; and then, before this is used, it matical book, took such a fancy to the study, that, by the would be proper to take the distance of the two objects natural strength of his genius, without any instructor, he first nearly by a fore-staff, and from thence accordingly soon made himself master of that, and of every other of the 'kind he could borrow or procure in English; and finding there was more to be had in Latin books, under all imaginable discouragements, applied himself to the study of that language, till he could pretty well under
12 UHR stand an author on these subjects; after which, the first time I ever saw or heard of him, to my knowledge, he came to borrow Sir Isaac Newton's Principia of me. Inquiring of hiin hereupon who he was, I was indeed astonished at his request; but after a little discourse, he soon became welcome to that or any other book I had.
H н This young man, about 18 months since, told me he had
G for some time been thinking of an instrument for taking
want the distances of stars by reflecting speculums, which he
B believed might be of service at sea; and not long after he showed me a common sea Quadrant, to which he had fitted two pieces of looking-glass in such a manner as
K brought two stars, at almost any distance, to coincide; the one by a direct, the other by a reflected ray, so that the eye could take them both together as joined in one,
frys sutine while a moving label or index on the graduated arch marked exactly half their distance: for I need not say
perfume that the variations of the angles of reflection from two speculums are double to the angle of the inclination of their planes, and therefore gives but half the angle or arch of the distance, wiich is the only inconveniency
you that appears to me to attend this. But as it may be made so simple, easy and light, as not to be much more unwieldy or unmanageable, though of a considerable length, than a single telescope of the same, that inconveniency will be abundantly compensated.
: The description of it, as he proposes it, and has got one made, is nearly thus, which he is willing I should communicate to thee, if possibly it may be of service.
To a straight ruler or piece of wood, A B, of about three inches in breadth, and from 40 to 45 in length (or
510 of any other that may be thought convenient), with a suitable thickness, an arch or limb, A C, of about 30 de
L grees to the radius, K L, is to be fixed. To the upper end of the piece A B, a piece, D D, is to be morticed, and in it the centre K taken, so that o p may be about to set the index. This screw, at land, would be highly six inches, and the angle K O P about 40 degrees. On useful, but at sea it cannot be wrought, while the instruthis centre K, the ruler or index K L is to move, having ment is directed by the same person, though, as the moa fiducial edge below answerable to the central point, to tions of the inoon and variation of the angle is but slow, cut the graduations on the limb. On the upper end of it may be brought to exactness by several trials in the this index a speculum of silvered glass, or rather metal, intervals of direction. The instrument, as above des. exactly plain, E F, of about three inches in length and cribed, will not take an angle of much above 50 degrees, two in height, is erected perpendicular to the plane of which, for the purpose intended, may be fully suffithe index, and also nearly at right angles with its sides, cient. But if the speculum E F be made to take off and the plane of the reflecting surface standing exactly over put on, and the end of the index at K be so notched as the central point. At the end B, of the piece AB, ano- to turn that speculum from its first perpendicularity, to ther speculum of glass is to be in the same manner erect. make an angle of about 25 degrees, it will then take any ed, which may be somewhat less than the other, with a distance to 100 degrees. square or oblong spot in it unsilvered, that a star, by a By this description it may be thought that the utmost direct ray, may be seen through it; and the back of this accuracy will be required in making the instrument: yet, speculum should be guarded with a thin brass plate, of all that ever have been invented of so curious a kind, with an aperture in it equal to the unsilvered part of the it will probably be found to demand the least; for providglass; the edge of the aperture toward H to be exactly ed the speculums are good, on which the whole depends, straight, dividing between the silvered and unsilvered if the first E F be set truly over the centre, the limb part of the speculum, and standing in the line of the axis well graduated, and the other speculum be also set perof the telescope. This speculum is to be set at an angle pendicular, there can, I think, be no other error but of about 30 deg. with the square of the piece A B, or at what the instrument itself will easily rectify: for if it be 110 deg. with the sides of it. Upon the piece A B, the directed to one star, and that be taken, at the same time,
INVENTION OF THE QUADRANT.
both by a direct ray through the glass G H, and by a re- thy accurate tables, have obtained the great desideraflection from E F, both exactly coinciding at 0, it is evi- tum, and all that can in this way be had from our sateldent that then the speculums are exactly parallel. -lites. And if the method of discovering the longitude And if this falls not precisely when the index cuts 0 de- by the moon is to meet with a reward, and this instrugrees, if the variation be noted, this constantly added or ment, which, for all that I have ever read or heard of, is subtracted, according as it falls, will fully rectify all other an invention altogether new, be made use of, in that case errors. So in fixing the speculum E F to another angle, I would recommend the inventor to thy justice and noas has been proposed, the like method may or must be tice. He now gets his own and family's bread (for he is taken, viz. to observe two stars at the distance of about married) by the labour of his own hands only, by that 45 or 50 degrees, by the speculum, in its first situation, mean trade. He had begun to make tables of the moon, and then the same stars by it again in its second, and the on the very same principles with thine, till I lately put difference of the intersection of the index on the limb a copy of those that have lain so many years printed, but being noted, and constantly added to the arches taken not published, with W. Inny's, into his hands, and then, in the second situation, will give the true distance.- highly approving of them, he desisted. We both wish This method of observing one and the same star, in the very much to see thy tables completed, and ushered infirst manner, or two stars in the second, as has been men- to the world by thy own hand. On thy receipt of this I tioned, will also rectify errors even in the speculums: for shall hope for a line, with thy thoughts on it, which, the line of the ray KO is in all cases constantly the same; however they prove, will afford a pleasure to and, upon the whole, I may safely say the 'instrument
Thy real friend, J. LOGAN. will be found much more certain in practice than at first Pennsylvania, May 25, 1732. it may appear in theory, even to some good judges. But I am now sensible I have trespassed in being so particu
To the Royal Society. lar when writing to Dr. Halley; for I well know that, to Gentlemen,-As none are better able than the Royal a gentlemen noted for his excellent talent of reading, ap- Society to prove and judge, whether such inventions as prehending, and greatly improving, less would have are proposed for the advancing useful knowledge will been sufficient; but as this possibly may be communi- answer the pretensions of the Inventors, or not; and as I cated by thee, I shall crave leave further to add, that the have been made acquainted (though at so great a disuse of the instrument is very easy. For if the index be tance) of the candour of your learned society in giving set so near the distance of the moon and stars, and the encouragement to sach as merit approbation, I have, limb so held as to cut the body of the moon, upon di- therefore, presumed to lay before the society the followrecting the telescope to the star, her image will
, of ing, craving pardon for my boldness. course, be reflected on some part of the speculum G H. Finding by what difficulty a tolerable observation of There is no absolute necessity the star and moon should the sun is taken by Davis's quadrant, and that in using it, coincide exactly at the line
limiting the silvered and un- unless the spot or shade be brought truly in the line of silvered part of the latter speculum; for the transparent the horizon-vane, the observation when made is good part of that glass will often reflect the moon's image suf for nothing, to do which requires much practice, and at ficiently for the telescope to take it, and if her limb in best is but catching an observation; considering farther that and the star exactly coincide near it, it may be suf- the smallness of the 60° arch and the aptness of the ficient, though the nearer to that line the better. Now wood to cast, which makes often little better than guess their distance being found, the tables that give the work; I therefore applied my thoughts upwards of two moon's place may be depended on for her diameter and years since, to find a more certain instrument, and conher latitude, which last being known, there are three trived the following improvement, as I think, in the sides of a triangle given to find the angle at the pole of make and use of the bow, viz. the ecliptic, which, compared with the star's longitude,
в. determines her place for that instant: for, in respect to her latitude when she is swiftest in motion, when nearest her nodes, and when the inclination of the orb is greatest (if these could all happen together), yet the va. riation of her latitude, in the space of one hour, equal to 15 deg. of longitude on the earth, if a star be taken somewhat near the ecliptic, and not very near the moon, will not alter the angle at the pole but a very few seconds. The nearness of the speculum G H is no disadvantage, because the rays come reflected in the same manner as they come direct. It may be needless to add that, when practicable, the moon should be taken when near the meridian-or that the instrument will equally take the distance of the sun from the moon, when visible, as she often is, in the day-time; for which purpose there must be a place made at M for a darkening glass, to be fixed The quadrant is to be numbered from each end to 90 there when necessary, and the telescope directed to the at the other, as in the figure. The sight and glass vanes moon. Nor need I add, that the same instrument will are the same with the common, excepting that the glass very well serve for taking the distance of any two stars, should be larger and, I think, it would be better if a comet, &c. always taking the brightest by reflection; ground to the segment of the cylinder. The horizon all which is obvious. But I must further observe, with vane should be like that in the figure thereof; having pleasure, that if we do not quite mistake in all that has three holes IKL, one hole I to fit on the centre of the been said here, there is now a method found by it to ob- quadrant A, the other two KL to see the horizon through, tain what is equivalent to a bodily appulse of the moon whose length across the vane may be $ of the radius AB to a fixed star, or to the sun at any moment when visi- or more; the horizon vane should be a little hollowed, ble, which indeed might be wished; but could scarce be answerable to the curvature of the circle DAE, or cyhoped for by any means to be used at sea, and
therefore, linder whose semi-diameter AH is about 7-11 of AB the if the longitude could ever be expected to be determined radius of the quadrant. by the motions of the moon (to which end J. Flamstead's In observing with this quadrant at sea let the sight and and thy more assiduous labours in observing her, have, I glass vanes be kept nearly on the same numbers, or at suppose, been principally leveiled), and this instrument equal distances from the ends of the arch, and then it be duly made to answer what is proposed, as it may be will be sufficiently exact to bring the spot and horizon framed light and easily manageable, thou wilt then, with in a right line, or any part of the horizon vane, by mov
INVENTION OF THE QUADRAYT.
tocīl x 2812
ing the vanes nearer together or further apart, the mid Thomas Godfrey having under the greatest disarivandle of the horizon vane being parallel to the horizon, tages (as I observed in my first letter to Dr. Halley, givthen the zenith distance will be the sum of the distances ing an account of the invention of the reflecting instruof the vanes from the ends of the quadrant arch. For, ment) made himself master of the principles of astronomy putting r-the radius of the quadrant, a=the distance and optics, as well as other parts of the mathematical of the spot from the middle of the horizon-vane, s-the science, applied his thoughts to consider the instrument sine and c-the cosine of half the sun's altitude, unity used in that momentous part of business, navigation. He being radius, the sine of the error will be nearly equal saw that on the knowledge of the latitude and longitude 28aa
of the place a ship is in, the lives of thousands of useful and therefore, when greatest, (which is subjects as well as valuable cargoes continually depend; 14
that for finding the first of these, certain and easy me. when the zenith distance is 00,00, or 47° 45') of the dis- thods are furnished by nature, if observations be truly tance of 1-16 of the radius of the quadrant from the made. But Davis's Quadrant, the instrument used by middle of the horizon-vane, it is but 1-30; I would ad- British navigators (though seldom by foreigners) he vise to bring the upper or lower edge of the spot, and perceived was attended with this inconveniency, that not the middle and horizon, in a right line, and then sub- the observer must bring the shade or spot of light from tract or add 16 minutes for the sun's seini-diameter from the sun, and the rays from the horizon, to coincide exor to the zenith distance given by the vanes.
actly on the fiducial edge of the horizontal vane; that NB. There should be an a Howanc for the observer's though this can be done in moderate weather and seas, height above the surface of the sea, by subtracting 4, 5, with a clear sky and when the sun is not too high, with. or ő minutes. A table of this kind would not be amiss out any great difficulty; yet, in other cases, it requires on the back of the quadrant.
more accuracy, than can in some junctures possibly be There may be some graduations put on the staff near applied, and more time than can be allowed for it. the centre to be cut by a plumb-line hung, or a pin put In European latitudes, or to those in the northern trointo a small hole for land observations. One of these pic, when the sun is in the southern signs and near the quadrants, between 18 inches and 2 feet radius, if well meridian, he rises and falls but slowly. Yet in voyages graduated, will be sufficient to take the sun's zenith dis- to the East and West Indies, of which very many, espetance within two or three minutes.
cially to the latter, are made, he is at noon often and for Succeeding so well with the sun, encouraged me to many days together, in or near the zenith; and when apundertake what appeared a more difficult task, the find- proaching to, or leaving it, he rises and falls, when he ing some way to take the altitude of the stars at sea has declination, faster than even at the horizon. For it is (when the horizon may be seen) better than by the fore well known to persons acquainted with the sphere, that staff, which, I concluded, must be by bringing the two when his diurnal course takes the zenith, he there rises objects, horizon and star together.' I first considered and falls a whole degree or 60 minutes in 4 minutes of one reflection; but the faults of Davis's quadrant were time, so that the observer has but one minute to come here enlarged, which is chiefly the flying of the objects within 15 minutes of the truth in his latitude; while in a from each other by the least motion of the instrument. middle altitude, as 45 degress, he is at noon above fire
I then examined what two reflections would do, minutes and a half in time in rising or falling one single which perfectly answered my desire, being equally use- minute of space, the odds between which is more than ful in taking the distanee of stars from each other, and 8 to 1. also from the moon, and I believe practicable at sea; I say all these things are well known to astronomers, for I found that when one star was made to coincide by and yet perhaps no parts of the world require more es. two reflections with another, the distance of those actness in taking the latitude, than is necessary in roya: stars would be double the inclination of the reflecting ges to the West Indies; for it is owing to the difficulty planes, as may be easily demonstrated.
of this that vessels have so frequently missed the Island I see but one fault in this instrument, and that is, that of Barbadoes, and when got to the leeward of it have three feet radius in this has a graduation no larger than been obliged to run down a thousand miles farther to a quadrant of 18 inches radius. I hope Dr. Halley has Jamaica, from whence they can scarce work up again in received a more full account of this from I. Logan, esq. the space of many weeks against the constant trade therefore, I shall add no more than that I am
winds, and generally decline to try for, or attempt it. Gentlemen, yours &c.
But farther, as the latitude cannot be found by any
T. GODFREY. other method that our mariners are generally acquainted Philadelphia, Nov. 9, 1734.
with, than by the sun or a star on the meridian; it is ob.
vious that in a cloudy sky, when the sun can but now A further account of Thomas Godfrey's Improvement of and then be seen, and that only between the openings of Davis's Quadrant transferred to the Mariner's Bow. the clouds for very short intervals, which mariners know
frequently happens; as also in high tempestuous seas, Being informed that this improvement, proposed by when, though the sun should appear, the observer can Thomas Godfrey of this place, for observing the sun's scarcely keep his feet by any means; I say on these ac'altitude at sea, with more ease and expedition than is counts, it is obvious that it would certainly be of vast practicable by the common instrument in use for that advantage to have an instrument by which an observapurpose, was last winter laid before the royal society, in tion could also be, as it were, snatched or taken in much his own description of it, and that some gentlemen, less time than is generally required in the use of the wished to see the benefit intended by it more fully and common quadrant. clearly explained, 1 who have here the opportunity of Thomas Godfrey, therefore, considering this, applied knowing the author's thoughts on such subjects, being himself to finding out some contrivance by which the persuaded in my judgment, that if the instruinent as he necessity of bringing the rays from the sun, and those proposes it be brought into practice, it will in many from the horizon to coincide (which is the most difficult cases be of great service to navigation, have, therefore, part of the work) on one particular point or line for a thought it proper to draw up a more full account of it centre, might be removed. In order to which, he conthan the author himself has given, with the advantages sidered, that by the 21st, 3 element, Euclid, all angles attending it, which if approved of by better judgments, of the periphery of a circle, subtended by the same seg to whom what I offer is entirely submitted, it is hoped ment within it, are equal on what ever part of the cir the use of it will be recommended and further encourag- cumference the angular point falls; and therefore, if in: ed, as well as the author. The rise of the improvement stead of a quadrant, a semicircle were graduated to 90° with its convenience, as also a deseription of it, are as only, accounting every two degrees but one, this would follows:
effectually ansvor; for then if an arch of the same circle
INVENTION OF THE QUADRA, T.
were placed at the end of the diameter of the instrument, EDC, though both are subtended by the same line BD; every part of the opposite arch would equally serve for for their differences are the angles BAD and BED. taking the coincidence of the rays above mentioned. But such an instrument would manifestly be attended with great inconveniency; for it would in great altitudes be much more unmanageable, and the vanes could not be framed to stand, as they always ought, perpendicular to the rays. He, therefore, farther resolved to try whether a curve could not be found at the centre of a quadrant which would, at least for a length sufficient to catch the coincidence of the rays with case, fully answer the intention.
A curve that in all its parts would, in geometrical strictness, effect this, cannot be in nature, any more than one and the same point can be found for a centre to different circles whose circumference are not parallel. It
BD is certain that every arch on the limb may have a circle that will pass through the centre and be a locus, or geo- Therefore this inequality was likewise to be considered, metrical place for the angle made by that arch to fall on, ed on the ratio
of 7 to 11 for
the radius of the curve to
and compounding both together, Thomas Godfrey pitchbut then every arch has a different one from all others, as in the figure.
the rad. of the instrument, which is 6.3636 to 10. But on further advisement he now concludes on 6 6-40, and
a curve of this radius, of an inch on each side of the cenC
tre to an instrument of 20 inches radius, or of 1-20th of the radius whatever it be, will in no case whatever (as he has himself carefully computed it) produce an error of above 57", and it is very well known that navigators do (as they very safely may) slight a difference of one minute in latitude.
This radius is the true one for the circular place to an A
arch of 77° 15' and the variation from it is nearly as great at 90° as at any arch below it, the greatest below being at about 44°, which is owing to the differences expressed by the last figure above, and not to those of
the curvatures or circular places. D
Yet this variation of 57 seconds arises only when the spot or coincidence falls at the extremity of the horizontal sight or vane, or whole inch (in an instrument
of 20 inches rad.) from the centre and then only in the Let ABC be the quadrant, and AB, EF, GH be taken altitudes or arches of above 44 or 90°, and in these, at as arches of it. Circles drawn through each two of these the distance of half an inch from the centre, the variarespectively, and through the centre C as a third point, tion is but | so much, viz. about 14" and at # of an inch will manifestly be such loci or places: For every pair of not 4". At the centre it is precisely true. Therefore, these points stand in a segment of their own circle, as an observation may be taken with it, in one-fourth of the well as on a segment of the quadrant, and therefore by time that Davis's quadrant, on which three things must the cited 21, 3 el. the angles standing on these first seg- be brought to meet, in a general way requires. ments will every where be equal at the periphery of Considering this, and the vast importance of such their respective circles, and their radius will always be dispatch, in the case of great altitudes or of tempestuous equal to half the secant of half the arch on the quadrant. seas, or beclouded skies, it is presumed, the instrument In the circle CEDF (for instance) the angle CED is right thus made, will be judged preferable to all others of quadrant, because in a semicircle; CE is the radius of the kind yet known. the quadrants, ED the tangent of the angle ECE-| the Some masters of vessels who sail from hence to arch EF; and CD is the secant of the same the diame- the West Indies have got some of them* made, ter of the circle CEDF, and therefore its radius is half as well as they can be done here, and have found so that secant.
great an advantage in the facility and in the ready use of Now, from the figure it is plain, that in every small them in those southerly latitudes, that they reject all arch the radius of their circular place will be half the others. It can scarce be doubted, but when the instruradius of the quadrant. that is, putting this radius=10, ment becomes more generally known, it may, upon the the other will be 5 and the radius for the arch of 906 Royal Society's approbation, if the thing appears worthy (the highest to be used on the quadrant) will be the of it, more universally obtain in practice. It is now four square root of half the square of the radius=sine of 450 years since Thomas Godfrey hit on this improvement; for –7.071; and the arches of the centre, drawn by these his account of it, laid before the Society last winter, in two radii are the extremes, the medium of which is which he mentioned two years, was wrote in 1732; and 6.0355. And if a circular arch be drawn with this radius in the same year, 1730, after he was satisfied in this, the 1-20th part of the length of it, that is, in an instrument applied himself to think of the other, viz. the reflecting of 20 inches radius, the length of one inch on each side instrument by speculums for a help in the case of longiof the centre, affording two inches in the whole to catch tude, though it is also useful in taking altitudes; and one the coincidence of the rays on, which must be owned is of these, as has been abundantly proved by the maker, abundantly sufficient; the error, at the greatest variation and those who had it with them, was taken to sea, and of the arches, and at the extremity of these two inches, there used in observing the latitude the winter of that will not much exceed one minute: But in fixing the cur- year, and brought back again to Philadelphia before the vature or radius of this central arch, something further end of February, 1730-1, and was in my keeping some than a medium between the extremes in the radius is to months immediately after. be considered; for in small arches the variation is very small, but in great it equally increases as in the figure • Godfrey's instruments. where it appears the difference between the anglesABC † That is, I suppose, being "satisfied,” that he had and ADC is much greater than the difference EBC and I made a real improvement in the Quadrant.
INVENTION OF THE QUADRANT.
*It was indeed unhappy, that, having it in my power, vation; and as deserving to be ranked, as well as his faseeing he had no acquaintance nor knowledge of per- ther, among the curiosities of Pennsylvania. -MS. Letsons in England, that I transmitted not an account of it ter of the Rev. Dr. Eliot, of Boston, to the Author.
But I had other affairs of more importance to It is worthy of notice, that the use of the Quadrant in me; and it was owing to an accident which gave me question was confined to the English nation until the some uneasiness, viz. his attempting to publish some ac- year 1736, when M. D’Apres de Mannevillette, the great count of it in print here, that I transmitted it at last, in maritime Geographer, employed it on board a French May, 1732, to Dr. Halley, to whom I made no doubt but ship; and on his return to France, one of the earliest the invention would appear entirely new; and I must objecis of his attention was to state, in a public print, own I could not but wonder that our good will at least his high estimation of the curious instrument. He thus was never acknowledged. This, on my part, was all the had the honour of introducing to his countrymen one of merit I had to claim, nor did I then, or now, assume any the most valuable inventions of the age. other in either of these instruments. I only wish that the ingenious inventor himself might, by some means, be taken notice of, in a manner that might be of real advan
PITTSBURG MANUFACTURES. tage to him.
There needs not, I suppose, much more of a description of the instrument than has been given. I shall on The indefatigable and enlivening spirit of industry, ly say that the bow had best be an arch of about 100 de- which distinguishes Pittsburg and its vicinage, has regrees well graduated and numbered both ways; the ra- cently brought into operation the "Fort Pitt Glass dius 20 or 24 inches; the curve at the centre to be one- Works," situated about a mile from the city. Messrs. twentieth of the radius on each side, that is, one-tenth Price, Curling, & Co., the enterprising proprietors of of it in the whole; the radius of that curve 64-100 parts this establishment, have, within a few days past, produc: of the radius of the instrument; that the glass for the so-ed the first specimens of their manufacture, which afford lar vane should not be less, but rather larger than a silver ample evidence of their skill, and of the perfection to shilling with its vertex very exactly set, and that the utmost which their fabric will attain, when they shall have surcare be taken to place the middle of the curve at the mounted the obstacles incident to the first essays in an centre exactly perpendicular to the line or radius of 45 undertaking resembling the one on which they have ad. deg. as the observer must also take care that the two ventured. The articles which they have already comvanes on the limb be kept nearly equidistant from that pleted, are equal in quality and appearance to any, in a degree. To which I shall only add, that it may be best similar branch of manufacture, that have been produced to give the horizontal vane only one aperture, not two. in the Western country. The glass is of a beautiful transThe rest, I suppose, may be left to the workman. Thus, parent whiteness, and so excellent in texture and polish, doubting I have already been too prolix on the subject, that it might bear off the premium at any exhibition of to which nothing but a sincere inclination to promotc domestic manufactures, although opposed by the posiany thing that might contribute to a public benefit, and tive celebrity of Boston, and the asserted superlative exto do some justice to merit, could induce me, I shall on- cellence of England. ly request that what I have here offered may be con The founders of the "Fort Pitt Glass Works" merit strued by that intention.
every encouragement for their establishment. It is their
J. LOGAN. intention to conduct it, so as to acquire for its producPhiladelphia, June 28, 1734.
tions a character equal to that of any manufactory of a P.S. (By the Editors of the Magazine.] It is easy to similar kind in the United States; and, with the skill and see, by a careful perusal of these two letters, and that in experience which they are admitted
possess, and the our last Magazine, the progress of this invention, and spirit with which they have entered upon their enterhow far Mr. Godfrey ought to be considered as the in- prise, they may confidently anticipate success. It is our business to give impartial accounts of
Mr Price, one of the proprietors, was engaged in the facts and transcripts of authentic papers.
manufacture of glass at the works of the late Col. O'Ha. after that, is to judge for himself. For our own part; "Fort Pitt.” His predilection for his early pursuits and
ra, when our flourishing emporium bore the name of we have no hesitation in pronouncing Mr. Godfrey the real original inventor of this famous and useful instru- place of residence, has induced hini to revive, in the new
works, of which he is one of the builders and proprietors, the name that attached to our Western Birming
ham in the olden time. The subjoined extracts are from “Miller's Retrospect.”
Near the “Fort Pitt Glass Works,” Messrs. Frost and - Alderman Ilillegas, of this city, (Philadelphia) Vodrey, from Staffordshire, England, have within a few knew Godfrey. He says he remembers to have heard, months, since the commencement of their undertaking, perhaps 50 years ago, that, as Hadley had obtained the brought the manufacture of earthen ware into successful patent, complete justice could not be done to Godfrey; operation. The writer of this notice was invited, a few but that the Royal Society, thinking his ingenuity ought days since, by some friends of these gentlemen, to visit to be rewarded, either subscribed for him as individuals, the manufactory and examine its productions. The reor gave him out of their funds, £200 sterling: and know- sult of the examination was very gratifying to all the viing his infirmity (for it seems he was apt to indulge in in- siters. It is, indeed, surprising to observe to what a detemperate drinking), they thought it better to send the gree of perfection the spirited manufacturers have alreaamount in household furniture than in cash, and, inter dy attained, in the execution of their ware. Considering alia, sent him a clock, which the Alderman remembers the numerous and obstinate difficulties which they have to have seen."
had to encounter, in obtaining materials, adapted to Godfrey had a son, Thomas Godfrey, jun. who, in their purposes, and putting into operation the incipient 1765, published a volume of Juvenile Poems. The young processes of a species of manufacture heretofore entirely man is spoken of, by the writer of the preface, as pos- unkown to the Western country, they have obtained a sessing great natural endowments, with but little culti- success, which is at once honourable to themselves and
auspicious for the manufacturing interests of Pittsburg. All these circumstances of Mr. Logan's complaint, As soon as they can procure a competent supply of suitand almost every thing that follows to the end, except able clay, and a sufficient number of artisans to execute the directions for making the instrument, are left out of all the various parts of the manufacture, they contemthe account published in the Philosophical Transactions, | plate the fabrication of earthen ware, in all respects siwhich strengthens the conjecture that justice has not milar to that for which Staffordshire is so much cele. been done to the original inventor.