Sidebilder
PDF
ePub

265

[ocr errors]
[ocr errors]

RAM 10 HTƏ NEW MARROWAYNIDOWL VA Those who have not made the ex- because of the frequent turns they periment of the strength of a man, are obliged to make in the canals, to push horizontally with the arms, and to avoid running against each or to draw a horizontal cord in walk other. 6 odt ti mu t atoes 919 ing, the body dbeing linclined for- 10 de

à It remains for me, in the last wards, whether the cord be fastened

place, to compare the strength of towards the shoulders tovi about the

men with that of horses in drawing, middle of othe body (for the effort

which are the strongest of all draw will be no greater) in the same in elination of the body, since the sines

ing animals, but as it does not enof inclination and their complements

tirely depend upon their weight, as are always in the same ratio), cannot

that of a man does, but principally

on the muscles of their body, and on persuade themselves that the whole strength of a man is reduced to draw

the general disposition of its parts, only 27lbs. with a horizontal direc

which have a very great advantage

in pushing forwards, we must be tion.staNoti but a man, being bent,

content with the common experican sustainta much greater weight

ment, that a horse draws, horizonthan 27lbgul seeing, it the line PH

tally, as much as seven men ; and

tout made with HF an angle of 45 degrees, dit is certain that the weight

thus a horse can draw horizontally ofs the body would sustain 70lbs.;

only a little less than 200lbs. Not but as the would be bent according

but that, when loaded, he can draw to a lined as AB, which would be

a little more; but it is but little in

proportion to our idea of the great much more inclined to the horizon

strength of this animal. But as it than 45 degrees, it is certain that,

is usually considered as being apfar fronillbeing able to walk, he

plied to some wheel-carriage, such would hardly berable to sustain it. The same demonstration serves

as carts, we cannot make a just estialsol to show, that a man will have

mation of it, because, on a smooth

and horizontal plain, they need no much more strength to draw in walk

more force than is necessary to over. ing backwardsi than forwards; for,

come the friction of the axle-trees. in this situation of the body, the line

We may observe again, that three PCH, fig. 3, which passes from the

men will do more than a horse in end of the feet, P, through the cen.

carrying a burden up a steep hill tre rof gravity, C, and whereon de

for three men, loaded with 100lbs. pends the augmentation of the force,

each, will rise more easily and will be always more inclined to the

quickly than a horse loaded with horizon than the sdine of the body,

300lbs., which comes from the disACB, quite contrary to what it is

position of the parts of the human in the preceding position. But this

body, which are better adapted to manner of drawing could not be put

ascend than those of a horse. in practice, Tunless it was only to draw a cord, the mareontinuing always in the same plane; and one should not fail of putting one's self in tliis posture in such a case, for

NEW HArrow. nature and experience have taught Mr. Finlayson, of East Lothian, us to take always all possible advan- has obtained a patent for a New tage in common operations. It is Harrow,called Self-cleaning,'which for the same reason, also, that our is an important improvement in the mariners, and, in general, all who cultivation of land. Its chief merits rowi on the seas always pull their are, that it requires lees labour than gars from before backwards, for they the common harrow, that it destroys have miich more force than if they the weeds deeper, that it throirs pushed them forwards, as the gon- thein on the surface without becomdoliers of Venice do, for which I see ing choked, that it pulverizes the nog other reason than that of seeing earth more effectually, and that it before them; which is much more can, in a moment, be regulated to necessary for them than grent foree, work at any necessary depth.

[graphic]

at A may

have

at B

as soon as anyone take the angle of

manner, viz.

266

dvob
" REAPING CORN.

911.7.-ATLOIA ON THE IMPROVEMENT OF LICHT and of a conicate

what

AAA24
vin HOUSES ;

ihought proper :
BY SIR
JOSEPH
SENHOUSE. Uit!

þeing 100, 150, or 200 feet distant, I
Sır,

Although great improvements would recommeód three or more smaller bave, of late years, beeo made through lights to be seen a few leagues at seal but the British dominions upon Light So long as these last-melitioned are not Houses,

yet

+ I think it is possible to seen, the observer may conclude he is make farther progress in so useful and a considerable distance from it; but, Décessary a building. "

one of them is perceive In the first place, I would propose able, he need only that every light-huuse shouid have a altitude between it and the great one, different colour, as red, yellow, blue, and iu a table calculated on purpose &c., by which means they would be beforehand, he will find the distance immediately identified at night, as soon he is from

the light-house by an easy as perceived, which cannot so certainly and expeditious method, sufficiently be done if they are all alike in that exact for his purpose. respect,

99M 10+Tam, Sina Tui s1b490 d' In the next place, I would recom

192d Your well-wisher, og llama mend that they should be so constructed € 1,3893491 10 -69990919 Jo. ŠENTLOUSEDÍ as tot only to ascertain the situation Heasingham Hall, near Whitehavenge of headlands, harbours, &c., but also 3 iu ? June 8th, 1825. b To jelom to determine the distance the observer vei fi valitsus su raun stadgeomis may be from them, in the following setida con 200 bilerui

03492110 READING CORN. to zilitu 20.93)

or yd 699991190

The French claim the merit of
Thos 2014 H

new discovery of great importance

to agriculture in the advantages 18 s10qu

which, according to them, result 3291 Pislim 913 1910 y 10:1041 before it is perfectly ripe.

chis Eod yili

136 sonu vin

theory, which has just been promul.

gated by: M. Cadet de Vaux, origi120 ,

nates with M. de Salles, of the Agri

cultural Society of Beziers. The

? v following are the particulars i Corn Chi tiẼ ỞII.197 192 1 1 1 1 1 1 32

reaped eight days before the usual oferty 10:27

time is, in the first place, s secured Sij 2209 lui fii ut 1141423";D from the dangers wlrich threaten it ojni privindi non eith at that time this is only accidental; -115 3

but a positive advantage is, that the

grain is fuller, larger, finer, and that ZAHASIGA 331/31!! Ingin it is never attacked by the weeyil,

The truth of these statements has

been proved by the most conclusive 9. El dibudidati ini comparative experiments upon it a

, "; piece of corn, one-half of which was sitizonin us 311.4838491sia

reaped before the usual time, and 198919 7611 16 Varaosat1 the other half

at the degree of me

rity fixed by the ordinary practice. 52941 10 11011nij 1-10 Pin The first portion gave a hectolitre of Jonim ailem 29930 B13 thu ??opf corn more for half a hectar of

Pand. Afterwards, an equal quantity of flour from the wheat of each portion

was made into bread; that of the OUT

al corn reaped green gaye seven pounds

of bread more than the other in six

decalitres. Lastly, the weevil atSuppose the light-house to be érect-- tacked the corn which was cut ri

, ed accurding to the above elération, the other was exempt from it. The

[ocr errors]
[ocr errors]
[ocr errors]
[ocr errors]

.

[ocr errors]
[ocr errors]

ETC.

[ocr errors]
[ocr errors]

DAMIP-DETECTOR-IMPROVED AMERICAN

STEAM-BOAT,

267 proper time for reaping is that when York, and believing that you are the grain, on being pressed between ever willing to communicate any the fingers, has a doughy appear- thing that may tend to excite a anee like the crumb of bread just progressive improvement in the mahot from the oven, when pressed in chinery of this country, I have the same manner. Bl 9-9115 28 gatot je taken the liberty of forwarding it, ei sd sbulonos y 197192do 9,11992 in the hope that the hint may prove sud ti murt at sidsrsbi-003 6 serviceable a to some of your readers visvieq zi mari tu B 26 4002 25

who iq algas DAMP-DETECTOR,I ad euide ested in the subject than myself.

may be more practically interAn ingenious little instrument There have been several objections under this name, which denotes its raised (and perhaps justly so) against use, has been invented by Mr. Essex.steam-boats, as they are generally It consists of a small ivory box, about constructed ; and if by the adoption an inch in diameter, in which is a needle turning on a pivot, like the jections can be obviated, I apprehend

of this or any other plan, these obsmall pocket compasses. Being set it will be no little benefit both to to zero, it either proceeds or recedes the proprietors and the community as the surrounding atmosphere is at large. Without intruding further moist or dry.8 /Thus the state of the in your interesting pages, I shall subatmosphere may be ascertained by scribe myself, *19. Baltasis of invalids; but, perhaps, the greatest Yours, &c. 47910$ dor W. C. H. utility of the instrument can be ex- Kelvedon. perienced by travellers, since, by

From the Philadelphia Freeman's placing it for a few minutes only between bed-clothes for wearing

Journal of April 20.

THE TRENTON STEAM-BOAT. apparel, the motion of the index certainly detects the existence of The Trenton is constructed upon an damp, if there be any present coit

entire new model. Her boilers rest -9911 [1391199* a ti soted upon the guards projecting over the Jarmo mq 1990 toredlisiw.v109ds water from each side of the boat. -igito XIV 9b 1950 19d being This leaves the deck entirely unob

TRONDÓNÍMECHANICS INSTITUTION, structed, and forms what may be ssl' Sir, Allow me to request that y

t you

called a promenade deck. The will correet an error which appears in space usually occupied by the boilers your Magazine of the 16th inst. Speak- is converted into convenient and ele. bang of the new Theatre of the London gant dressing-rooms. Should any Mechanics' Institution, you say,(page accident happen to the boilers, the

IS The construction of the build- water would be thrown directly into sing does great credit to its designer, the river, and not in the least en- Mr. M William, one of the Vice Presi: danger the passengers. And what deals of the Institution.". Now it hap: is likewise important, the unpleasant pens, be one of the Vice-Presidents, yet this and annoying degree of heat in the

Theatre has been constructed under dining cabins is no longer felt. She 8the direction of the whole Committee was built at Hoboken, and it

may

be e of Mavagement, consisting of thirty; fearlessly asserted, the improvements baix persons, each of whom has an equal in the arrangement and disposition -iflaim to such inerit as the construction of her machinery are far greater

gof the Theatre in question may deserve. than any that have been yet made 10 spilor9112927 RT. M.WILLIAM,

since the first introduction of these bau Furpivál's Inn, July 26th, 1825.

boats into our waters. She might to tituoup les 09.1917 not unaptly be called the Water soittog do69 to 163113st w 10 Travelling Balloon. 91IMPRONED AVERICAN STEAM-BOAT. ebangkQYAS'Twas Tooking over an

MR. BADNALL'S PATENT THROWING newspapet short time "Since, I was inuch pleased with the following description of a new Steam--105 SIR, -kobserve in your Number Boat,' recently built at or near few of the 2d inst. some oliservations by

[graphic]
[graphic]
[ocr errors]
[ocr errors]

MACHINE.

[ocr errors]

268

REPLIES BY W. E. WIGITMAN, ON GUNNERY. “A Weaver,” as he signs himself, in has for years been gradually imWood-street, relative to my patent proved upon, and a most fascinating Throwing Machinery, and although model of which has been exhibited, I should feel a much greater satis- for Heaven knows how long, in the faction in replying to such kind of Tower of London. om die enim queries, were they authenticated by There is, however, one puzzling the proper signature of the writer, query still remaining unanswered, yet, as it will not occupy much time which I conceive your Correspondent in answering them, I will endeavour intended as a regular poser. « How do to set your Correspondent at rest in I calculate the velocity of my spindles?" as few words as possible.

or I must confess, that not feeling myIt is perfectly evident, from his 'self quite competent to answer this own statement, that he is not very question, I most unwillingly throw intimately acquainted with either myself on the mercy of your numes silk, wool, or cotton machinery, rous readers, sincerely hoping that otherwise he would know that from some one will be kind enough to one to three thousand revolutions of gratify

your Correspondent by a so the spinning spindle per minute are fution of this important question, but a common speed; and that in and at the same time assist me in so certain manufactories in different extraordinary a dilemma.

bleiv IoTied parts of England, that speed is in- 950 I have the honour to be, Sir, 929 creased to from four to six thousand 31169 116 Very faithfully yours, to revolutions; and I believe there are 120m 98 RICHARD BADNALL, JUN. instances in cotton-spinning where Your Correspondent may the number of revolutions per mi. probably be more inclined than ever nute considerably exceed even that.

to doubt the

accuracy of my asser: The allusion your Correspondent tions, when I assure him that I can makes to my reply to a letter which show him the bobbins upon

silksome tiine ago appeared in your winding engines revolving at Magazine, I shall pass over by merely greater speed than the limit he asremarking, that I am not in the

habit signs to that of Throwing Machinery, of making statements which I cannot thoroughly substantiate; and that bar goja, pobo oldsT 92T whatever may be the opinion of doubt tovallstol to dronotia either him or his friends as to the REPLY TO A LETTER ADDRESSED TO impracticability of such statements,

W. E. WIGHTMAN, ON GUNNERY. I should in future strongly recom- Sır, -In your valuable Magazine, mend their being perfectly certain of p. 132, vol. iv. I find a letter adsuch impracticability before they ven- dressed to me, signed «0.;” and as tured to publish any decided senti- it appears that I have not been sufments on the subject,

ficieritly intelligible, I will endeavour As to the remark of your Corre- to answer such parts of "0.'s letspondent, that the general opinion of ter as are answerable ; there are some the silk trade is adverse to my patent, which seem to me to require no

answer. Three kinds of barrels are is so: on this point I am perfectly in general use amongst sportsmen; easy.

viz. the Damascus, wire-twisted, and The Weaver in Wood-street is Stubbs - twisted. The Damascus likewise very much out of his mark barrels are the least expansive when when he supposes that my spindles fired, and the wire-twisted the most. are driven by toothed wheels ; and This may be known by placing lead the publication he has given to this hoops on the barrel that is to be error convinces me that he is as per: fired; the lead not being elastie, fectly ignorant of the nature of my does not contract with the barrel Throwing Machinery, as he is of any after firing, but plaintly shows how other, unless it be the wooden craut much the barrel expands under the ing mass of cumbrous matter which trial. This is how I to discover-the his friends have described to him ; difference.whick,eses through France and Italy, The Damascus barrels having little

[graphic]
[ocr errors]

REPLIES BY W. E. WIGHTMAN, ON GUNNERY, 269 or no expansibility when fired, do, in the above-named tables, there is so consequence, require to be bored great a difference in the cohesion of perfectly cylindrical. The charge, iron, of which gun-barrels might when propelled from such barrels, be made? All that I can say on this meeting with no irregular resistance point is, that a scientific man will or strait places, occasions, but easily find the proper bore for every little recoil, while the Stubbs-twisted, barrel by the assistance of leadon account of their flexibility, re- hoops. The process

is troublesome, quire to be bored wider at the breech, but certain ; it is done thus : Place that the shot may be partially debne hoop on the muzzle of the barlayed, .by, being driven into the rel, one about half-way down, and straiter part of the barrel, that it one a few inches from the breech ; may receive the full strength of the then place the barrel in a horizontal powder. The intention of boring direction, and fire it with touchguns in this manner is to counter- paper; and if the barrel regularly balance the expansion during the narrows from the bottom to the top, discharge ; for, as I previously ob- and is correctly bored, the hoops will served, the shot could not be dis- be found to have increased equally lodged with equal force when the in size with their first proportions, barrel yields to the expansion of the This is the best, nay, the only criexploded powder. The consequence terion, by which a barrel is to be of boring guns in this manner can- known when properly bored for not but be understood by the most shooting. The next consideration is uncircumspect observer ; for the ne- the length, which can only be regucessary dilatation of the barrel dur-lated by trial. The nearest rule for. ing the passage of the charge through the length, &c. of gun-barrels is as the straiter part, distends the fibres follows: the length should be 50 of the metal to a degree which their diameters of the bore, and the thickelasticity cannot always recover; and ness at the breech for a half-inch hence follow the repeated bursting's bore should be 1-8th inch, and of guns by a small addition to the should increase 1 - 16th inch in regular charge.

strength with every 1-8th inch inThe Table on the Cohesion and crease in the bore. The best method Strength of Metals, vol. 1. p. 71, of that I find to prove whether a barrel your Magazine, would have saved is perfectly cylindrical in the bore, *OP (had he seen it) such futile is by a lead plug, about one inch long, expressions as those regarding weld- and merely turned to fit the barrel, ed needles, hoop-iron, cast iron, and By gently forcing it through, it will brass : and with respect to a suc- show any irregularity in the inside. ceeding remark of his on the strength The uncertainty of the regular of barrels, where he says, " I do not shooting of guns, as will be seen by see why a barrel should shoot the better a schedule of Telloc Trigger's, prefor being thick; that is, a barrel as cludes the possibility of an answer thin as writing-paper should shoot us

to the last question. well as a barrel half an inch thick, pro

I am, Sir,

yours, &c. vided the force of the powder do not

W. E. WIGHTMAN.

i make any permanent alteration in the Malton, size of the bore." Let me ask him,

1991 too 97891 if any barrel were subject to this

dan REPLY TO HAMMER. geivodil permanent alteration every time the polling Page 132, Vol. IV.2 od 19 a 5-8thsbored

ŞIR, IN reply to Hammer," 1 fowling-piece would swell to a two

say that the best method of reinch duck-gun, ost/409 ton asal moving the lead from gun-barrels, is How is it possible to lay down to subject it to the boring bench

of a any specific rule for the boring of good workman ; forhe can so pack the gun-barrels, when, by reference to boring bit as to bore

out the lead

without touching the iron ; but when altvil gif Page 95, vol. 18.

IV. IT

o that cannot be done, a fine steel wire

[graphic]
[ocr errors]
[ocr errors]
[ocr errors]
« ForrigeFortsett »