Numb. 417. Beginning
For the Months of January and February, 1731.
I.A Catalogue of the fifty plants from Chelsea-Garden, presented to the Royal Society by the Company of Apothecaries, for the Year 1729; pursuant to the Direction of Sir Hans Sloane, Bart. Med. Reg. Præf. Col. Med. & Soc. Reg. by Isaac Rand, Apothecary, F.R.S.
II.A Description of the Water-Works at London-Bridge. By H. Beighton, F.R.S.
III.Epistola continens Historiam Calculi in Vesica sponte fracti, & per Urethram feliciter excreti; ad Illustrem Generosissimumque Virum D. Fred. de Thom, Serenissimo Duci Brunsvicensi et Luneburgensi a Consiliis, Oratorem ejus apud Potentissimum Magnæ Brittaniæ Regem, nec non R.S.S. a Laurentio Heisero, M.D. Prof. Botan. in Acad. Julia Helmstadii & R.S.S. conscripta.
IV.A Letter from the Reverend William Derham, D. D. Canon of Windsor, and F.R.S.
V.A letter to Cromwell Mortimer, M.D. Secr. R.S. containing several Experiments concerning Electricity; by Mr. Stephen Gray.
VI.Curvarum Hyperbolicarum, æquationibus trium nominum utcunque definitarum, Quadratura generalis duplici Theoremate exhibita à Do. Samuele Klingenstierna, Profess. Digniss. Math. in Acad. Upsal, & R.S.S. Communicante Do. Jacobo Stirling, ejusdem etiam Soc. Doctiss. S.
VII.Casus rarissimus Plica Polonicæ enormis à D. Abrahamo Vatero, M. D. Prof. Anatom. Wittemberg, & R.S.S. per D. Conradum Sprengell, Equitem, M.D. R.S.S. & Coll. Med. Lond. Licent. communicatus.
VIII.An Extract of a Letter from Sir Conrad Sprengell, M.D. R.S.S. & Coll. Med. Lond. Licen. to Dr. Mortimer; wherein he inclosed the foregoing Account of the Plica Polonica; together with an Article from the Breslaw Sammlung von Natur und Medicin, &c Geschichten, upon the same Subject, trnslated from the High-Dutch by Dr. Mortimer, R.S. Secr.
IX.An Account of an unusual Agitation in the Magnetical Needle, observed to last for some Time, in a Voyage from Maryland, by Capt. Walter Hoxton; communicated in a Letter to David Papillon, Esq; F.R.S.
1. A Catalogue of the fifty Plants from Chelsea-Garden, presented to the Royal Society by the Company of Apothecaries, for the Year 1729; persuant to the Direction of Sir Hans Sloane, Bart Med. Reg. Præs Col. Reg. Med. & Soc. Reg. by lsaac Rand, Apothecary, F.R.S.
351. ACER Fraxini foliis, serratis. Acer maximum; foliis trifidis & quinquefidis, Virginianum. Pluk. Phyt. Tab. 123. Fig. 4 & 5.
352.Agrimonia odorata. Cam. Hort.
353.Agrimonia officinarum. T. Inst. 301.
354.Agrimonia, minor; flore albo H. C. Boerh, Ind.
355.Anapodophyllon Canadense Morini. T. Inst. 239.
356.Apocynoides subhirsuta; floribus aurantiis.
357.Aracus, q. Vicia segetum; singularibus siliquis glabris. C. B. 345.
358.Brasica Orientalis, perfoliata; flore albo; filiqua quadrangular T. Cor. 16.
359.Brunella laciniata; flore elegantissimè sulphureo.
Boer. Ind. alt. 169.
360.Cassida Cretica; fruticosa; Catariæ folio;
flore albo. T. Cor. 11.
361.Cassida palustris, vulgatior; flore cæruleo.
T. Inst. 182.
362.Cassida orientalis; Chamædryos folio; flore luteo. T. Cor II.
363.Convolvulus Canariensis; longioribus foliis, mollibus & incanis. Pluk. Phyt. Tab, 325. Fig.I.
364.Daucus, quiPastinaca Œnanthes folio. Boccon. rar. 75.
365.Echinopus minor, annuus; magno capite, T. Inst. 463.
366.Frutex Afiicanus, Ambram spirans. Pluck. Phyt. Tab.183. Fig. I.
367.Galeopsis Hispanica; frutescens; Teucrii fo1io. T. Inst. 186.
368.Hedypnois annua. T. Inst 478.
369.Hedypnois Cretica, minor, annua. T. Cor. 36.
370.Hedypnois Hispanica, procumbens; magno capite. An Hedypnois annua, capite maximo. Boerh. Ind. alt. 93?
371.Heleniastrum; folio longiore & angustiore D. Vaillant. Acad. Reg. Par. anno 1720.
372.Heleniastrum feriùs florens; latiore folio; ramosissimum. An. Heleniastrum; folio breviore & latiore. Ejusdem Ibid?
373.Hieracium fruticosum, angustissimo, incano folio. H.L. Bat. 316.
374.Hieracium Pulmonaria dictum, latifolium, humilius; ramulis expansis.
375.Lamium Garganicum, subincanum; flore purpurascente, cum labio superiori crenato. Micheli. Hort.Pisan. 93. Tab. 32.
II.A Description of the Water-Works at London-Bridge, explaining the Draught of Tab. I.By H. Beighton, F.R.S.
THE Wheels are placed under the Arches of London-Bridge, and moved by the common Stream of the Tide-Water of the River Thames.
A B the Axle-tree of the Water-Wheel, 19 Feet long, 3 Feet Diameter, in which C, D, E, F, are four Sets of Arms, eight in each Place, on which are fixed G G G G, four Rings, or Sets of Felloes, in Diameter 20 Feet, and the Floats H H H, 14 Feet long and 18 Inches deep, being about 26 in Number.
The Wheel lies with its two Gudgeons, or Centers, A B, upon two Brasses in the Pieces M N, which are two great Levers, whose Fulcrum, or Prop, is an arched Piece of Timber L, the Levers being made circular on their lower Sides to an Arch of the Radius M O, and kept in their Places by two arching Studs fixed in the Stock L, through two Mortises in the Lever M N.
The Wheel is, by these Levers, made to rise and fall with the Tide, which is performed in this Manner. The Levers M N are 16 Feet long; from M, the Fulcrum of the Lever, to O the Gudgeon of the Water-Wheel, 6 Feet; and from O to the Arch at N, 10 Feet. To the Bottom of the Arch N is fixed a strong triple Chain P, made after the Fashion of a Watch-Chain, but the Links arched to a Circle of one Foot Diameter, having Notches, or Teeth, to take hold of the Leaves of a Pinion of cast Iron Q, 10 Inches Diameter, with eight Teeth in it moving on an Axis. The other loose End of this Chain has a large Weight hanging at it, to help to counterpoise the Wheel, and preserve the Chain from sliding on the Pinion. On the same Axis is fixed a Cog-Wheel R, 6 Feet Diameter, with 48 Cogs. To this is applied a Trundle, or Pinion, S, of fix Rounds, or Teeth; and upon the same Axis is fixed T, a Cog-Wheel of 51 Cogs, into which the Trundle V, of six Rounds, works; on whose Axis is a Winch, or Windlass, W, by which one Man, with the two Windlasses, raises or lets down the Wheel as there is Occasion.
And because the Fulcra of these Levers, M N, are in the Axis of the Trundle K, viz, at M or X, in what Situation soever the Wheel is raised or let down, the Cog-Wheel II, is always equidistant from M, and works, or geers truly.
By Means of this Machine the Strength of an ordinary Man will raise about fifty Ton Weight.
I, I, is a Cog-Wheel fixed near the End of the great Axis, 8 Feet Diameter, and 44 Cogs working into a Trundle K, of 41 Foot Diameter, and 20 Rounds, whose Axis or Spindle is of Cast Iron 4 Inches in Diameter, lying in Brasses at each End, as at X.
Z Z is a quadruple Crank of Cast Iron, the Metal being 6 Inches square, each of the Necks being turned one Foot from the Center, which is fixed in Brasses at each End in two Head-stocks fastned down by Caps. One End of this Crank at Y is placed close abutting to the End of the Axle-tree X, where they are at those Ends six Inches Diameter, each having a Slit in the Ends, where an Iron Wedge is put, one half into the End X, the other half into Y, by Means of which the Axis X turns about the Crank Z Z.
The four Necks of the Crank have each an Iron Spear, or Rod, fixed at their upper Ends to the respective Libra, or Lever, a 1, 2, 3, 4, within three Foot of the End. These Levers are 24 Feet long, moving on Centers in the Frame b b b b; at the End of which, at c 1, 2, 3, 4, are jointed four Rods with their forcing Plugs working into d 1, 2, 3, 4, four Cast Iron Cylinders four Feet three quarters long, seven Inches Bore above, and nine below where the Valves lie, fastened by skrewed Flanches, over the four Holes of a hollow Trunk of Cast Iron, having four Valves in it just over e e e e, at the joining on of the Bottom of the Barrels, or Cylinders, and at one End a sucking Pipe and Grate f, going into the Water, which supplies all the four Cylinders alternately.From the lower Part of the Cylinders d1, d2, d3, d4, come out Necks turning upward Arch-wise, as g g g g, whose upper Parts are cast with Flanches to skrew up to the Trunk h h h h; which Necks have Bores of 7 Inches Diameter, and Holes in the Trunk above communicating with them, at which Joining are placed four Valves. The Trunk is cast with four Bosses, or Protuberances, standing out against the Valves to give room for their opening and shutting; and on the upper Side are four Holes stopped with Plugs, to take out on Occasion, to cleanse the Valves. One End of this Trunk is stopped by a Plug i. To the other, Iron Pipes are joined, as i 2, by Flanches, through which Page:Philosophical Transactions - Volume 037.djvu/13 Page:Philosophical Transactions - Volume 037.djvu/14 Page:Philosophical Transactions - Volume 037.djvu/15 Page:Philosophical Transactions - Volume 037.djvu/16 Page:Philosophical Transactions - Volume 037.djvu/17
Page:Philosophical Transactions - Volume 037.djvu/59 "were as hard twisted, as so many Penny Cords; that one might easily have taken his for a Medusa's Head (and who knows, but that in ancient Times some such Locks as these might have given Rise to the Poetical Fiction of Snakes growing on the Head instead of Hair? Be that as it will, this is certain, it is a most odious Sight to look on."
IX. An Account of an unusual Agitation in the Magnetical Needle, observed to last for some Time, in Voyage from Maryland, by Capt. Walter Hoxton; communicated in a Letter to David Papillon, Esq; F.R.S.
ON the second of September, 1724, a little after Noon, being in Latitude 41° 10' N. and Difference of Longitude from Cape Henry in Virginia about 28° 00' E. the Weather fair, a moderate Gale, and smooth Sea, my Mate, who was on the Deck, came and told me, that the Compass traversed so much that he could not possibly steer by it: Whereupon I went up, and after trying it in several Parts of the Ship, found what he said to be true. I then had all my Compasses brought up, and placed in different Parts of the Ship, and in Places most remote from Iron, and, to my great Surprize, found them all in the same Condition; so that we could not steer by any of them. I then new touched some of them with a Loadstone, which I always carry with me; and left that should affect them, sent it out to the End of the Bowspreet; but I did not perccive that the new touching was of any Service, for they all continued traversing very swiftly, for about an Hour after I came on the Deck, and then on a sudden every one of them stood as well as usual. During the whole Time, the Ship had very little Motion; and I had an Azimuth Compass, and four or five others.
ERRATA which have escaped Notice till now.
NUMB. 415. p.378. l. 5. for majore read minore. Numb. 416. p.444. l. 8. from the Bottom,for dead read down. Ibid. l. 7. for ghostly read gastly.