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362

MR. HOWARD'S REJOINDER TO MR. SYMINGTON. the best and next best suggestions as to the old and expensive nrethod of putting the cause and method of preventing the tallow into the boiler was again resorted recurrence of steam-boiler explosions. It to. I began to observe, that for a few was understood, that no fewer than se- days after the boiler was cleaned no venty-four plans, suggestions, essays, priming occurred, and therefore ordered and lectures were handed in, but the the boiler to be cleaned once a week, and matter has not gone farther, at least the ever since we have had no priming but plans have not been made public, which on Friday evening and Saturday after the is much to be regretted, for from among dirt accumulates. The silt which occathe mass of useless matter which would

sion's this, is the finer portions of shale be produced, surely something towards taken up by the water in passing through effecting a cure would have come out. a coal-waste; it attaches itself to the

My object in noticing this subject is bottom and sides of the boiler in feathery to offer some remarks 'on the subject of flakes, which gradually extend far up

foaming,” known by the name of“ prim- above the water-line. That this is the ing" in this country. : As far as I can cause of the foaming, there cannot be a see, the Committee of the Franklin In- doubt; for when there has been any stitute have elicited nothing as to the unusual traffic in the mine from which cause of this phenomenon, nor given the boiler is fed to make the water dirlier any cure for it. They notice

very than cominon, then the priming begins feasible plan by Mr. Ewbank (the per- much earlier in the week; and, moreover, forated steam-pipe), but they do not tell I have often seen the priming produced if it prevents the foaming. Every person when the boiler was clean, by peas-meal conversant with high-pressure engines or horse-dung being put in to stop a leak. knew perfectly without looking in at a This favourite cure of our engine-men's window that a foaming commenced when cannot be used from the absolute certhe engine began to work, and that the : tainty that the engine will prime all that gage-cocks at that time would blow and the next day (moss is found to tighten waler, although the floats indicated the

a leak without priming). It would there. water-line to be considerably lower. I fore seem that ihis troublesome defect of have a large high-pressure engine under- many high-pressure engines arises from ground here, and I have been more than the river mud,* attaching itself to the commonly annoyed with prining, and sides of the boiler; but how it acts, I have tried various methods, but without must leave to be settled by those who effect; in the course of working out these have windows to look in and see. experiments, I have most certainly dis- I trust, sir, you will give these remarks covered the cause of the priming, but the a place in your useful pages, and I shall cure, in this case, although certain, is be glad if they elicit more practical renot a convenient one. I first attempted marks on the subject; and to separate the water from the steam after Your most obedient servant, it left the boiler by the means represented

L. LANDALE. in the foregoing sectional view, which is Wemyss Cottage, July 30, 1836. on a scale of half an inch to a foot. Above the boiler A (which is long and

MR. HOWARD'S REJOINDER TO MR. circular, with hemispherical ends,) was

SYMINGTON. placed a vessel or separator; A á into which the steam was admitted by the

Sir --In reply to Mr. Symington's last pipe B, the mouth of which was twelve

communication, I must, in the first place, inches above the bottom of the vessel A;

freely tender my apology for stating that alongside of this a small pipe C, leading

I had seen him at the King and Queen under the water-line, was placed, and

Iron-works, when (his own denial being the steam to the engine was taken from

quite sufficient evidence) such was not the top of the vessel A by the eduction

the case.

Even had it been so, I did not pipe E. My idea was, that when the mean for a moment to impute to him the foam entered the separator the steam

motive of having done so, as he strggests, would flow off at the top, and the water

I must say, gratuitonsly, for the prurpose would fall down by its gravity and get

of pirating my invention. But I williet into the boiler again by the pipe c; but

plain. In the spring of 1834, I was em Î was sadly disappointed ; the engine continued to prime as bad as ever, and

* The comminated shale of the mine was onde fine river silt, the same as this.

RAILWAY TRANSIT AND INLAND NAVIGATION.

363 ployed in fitting his Majesty's steam- the warm water from the condenser and vessel Comet with my patent vaporisers injecting it again amidst the steam, the and condensers; and the Admiralty pur- heat in the mean time having been abposed trying a wheel invented by Mr. stracted from it, in competition with Mr. Symington at the same time. On my Watt's invention, for the result is far, pointing out, however, the inconvenience very far inferior indeed, to that obtained and uncertainty of trial likely to result to by his improvement on the then existing both parties by this arrangement, it was steam-engine; yet I place myself on the very properly abandoned by the Admi- same ground with respect to others who ralty, and the wheel was subsequently attempted to practise, in combination with tried in the Alban. In the mean time I his process, any alterations in the arcalled on the manufacturer of the wheel rangement or details. In this position I at Bankside (Mr. Brough, if I remember presume Mr. Symington to stand with the name correctly), and he came to respect to myself. Rotherhithe to inspect my engine at work I

may

further state, that my specificathere. Again, by appointment, he came tion provides for such contingencies, with, and introduced to me, as I fully otherwise a patent is mere waste parchunterstood (and here must lie the error), ment; and that a description of both the Mr. Symington as the inventor of the method of vaporisation (by far the more wheel in question, to whom I explained important, by-the-bye,) and condensation my invention in every particular--the

is given

the last edition of Dr. Lardmore so as he was then interested in the ner's able treatise on the steam-engine, efficiency of it to propel his wheel. These and to which work Mr. Symington himfacts will, 1 doubt not, gire Mr. Syming- self alludes in his communication in ton a clue by which to discover the cause your No. 677. The specification further of my mistake.

states, that the result of the plan of conNow to the more important point at densation when employed with boilers, issue between us. Will Mr. Symington will be a very rapid and effectual constate, that he does not take the sanie densation of the steam, with the advantage principle or method of condensation as of continually returning to the boiler the that previously patented by me? Will he same water, or nearly so, and also a state, as he seems to insinuate, that I great reduction in the size of the air, have not caused the process to answer pump. completely, that is, I now say, as com

Your most obedient servant, pletely as any pre-existing plan of con

THOMAS HOWARD. densation whatever? And will he inform 7, Tokenhouse Yard, London, me where he has previously done so ?

August 24, 1836. Upon this evidence I will ground the validity of my claim to priority of invention.

(From the Times' Report of First Day's ProWhen Mr. Watt discovered and pa

ceedings of the Bristol Meeting of the Britented the splendid improvement of con

tish Association, August 22, 1836.)

The subjects arranged for discussion were densing the steam in a vessel apart from

two-on certain points connected with the the cylinder, he invented a principle or

theory of locomotive-carriages, and on the new method ; and no subsequent altera

application of our knowledge of the phenotion or even improvement upon it could

mena of waves to the improvement of the deprive him of his patent right during navigation of shallow rivers and canals. the term for which it was granted. Whe- Professor Mosley opened the first point by ther the condenser was placed in a well stating that there were many gentlemen preor in a garret- whether the steam was sent acquainted with the practical working of condensed by injection or external cold steam-engines, but the relations between the water (a material difference) —who, even

theory and practice were not perfectly underwith the most contracted view of justice,

stood. The piston of a locomotive-engine would deny that he was the inventor of

was pressed on either side, one resulting from

the friction on the road, and the other from the process, and legally and morally en

the passive friction of the engine itself. If titled to the benefit of it; provided, as it was lifted from the ground, a person enwas the case, his own arrangement

deavouring to move the wheels would find a proved perfectly efficient in practice. Ale

resistance equal to 150 lbs. The cause of though I do not pretend to place my the resistance was this—that the traction method of condensation, by withdrawing upon the engine induced additional friction

RAILWAY TRANSIT AND INLAND NAVIGATION.

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364

ŘAILWAY TRANSIT AND INLAND NAVIGATION. of the machinery, and that probably was Mr. Russell made some very lengthy, but one-fifth of the whole amount of friction.

very interesting observations, the substance If the engine moved without a train, there of which was this,—where canals did exist, would be a passive resistance ; if a train was there was no man but wished they should be attached to it, there would be induced a conducted in the most profitable manner. considerable friction of the machinery. There Newton's law had been confirmed, that the were, in fact, three causes of resistance resistance was in proportion to the square of the friction of the carriage, the passive re- the velocity.

The difference in the amount of sistance, the additional friction by the train resistance between a vessel drawn on a canal -the first and last varying according to the by a horse, trotting or cantering, was from weight of the train. On the other side there 108 to 136. He would read from a paper was the expansive force of the steam.' The

the results of various experiments he had quantity of work done was greater as the made, in which they would perceive a very velocity was less. Inelined planes on rail. curious fact as regarded the pace of eight roads he considered to be injurious., in trilly miles an hour. The table was thus :LiDr. Lardner said he had given a good deal

Lbs. of evidence before Parliament upon this sub- tri 4 miles an hour gave a resistance of.. 33 ject. In all inclined planes more steep than

6 ditto
ditto

91 7} ditto

ditto the angle of repose there was an unfavourable

265 8. ditto

ditto loss of power. The portion of mechanical

9 ditto
ditio

235 force expended in ascending the plane was 11 ditto

dillo

246 not repaid in the descent. Theoretically

12 ditto

ditto 15 ditto

ditto they might take adrantage of the accumulative matter as a deposit of momentum, and

But at the rate of 20 miles an hour the ves. make a perfect mechanical compensation,

sel skated along the surface of the water, and but that was not the case in practice, because there was scarcely any resistance at all. they were obliged to check the velocity in the

When a vessel was propelled at a great vedescent. He had never said, as had been locity and then stopped, it produced a wave represented, that inclined planes were not of varying in its form, according to the mass importance, because the friction in the ascent of the water, and he had followed such a was given back in the descent. When the wave a mile and a half; the velocity of the engine was descending, great part of its wave was uniform, and independent of the steam was going off in the safety-valve, there. velocity of the vessel. If the vessel was fore inclined planes were injurious. All the going four miles an hour, this wave would experiments led to the conclusion, that every go at the rate of eight miles an hour, and he effort should be made to attain as perfect a had seen a large wave overtake a small wave level as possible. Every departure from a and pass it. The waves never exceeded in level, though it saved a quantity of capital height the depth of the quiescent water. Vesin the construction of a road, entailed an sels at a slow velocity did not divide the everlasting expense. The result of some ex- water as was generally supposed, but pushed periments he had made was this—that in the it forward in the shape of a wave; but ordinary state of the roads, the force neces- where the velocity was greater than eight or sary on a level was 7lbs. per ton; but he nine miles an hour, the vessel did divide the found an extraordinary difference depending water. It was possible to bring the vessel on the state of the rails, a difference amount- completely upon the wave, and then you had ing in some instances to such an extent that scarcely any resistance. A velocity of bethe friction was reduced to 4 lbs. When it tween four and six miles an hour on canals rained and the rails were wet, he found the was unprofitable; beyond 11 miles an hour friction reduced to 4lbs., but as soon as the you had a high velocity, and comparatively rails became again dry, the friction was little resistance. He recommended a rectanagain 7 lbs.; he should therefore suggest, that gular canal where it was intended the velocity two watering-pots should be placed before the should be great, as by widening a canal with wlieels, so as to give the engine an additional sloping banks you increased the resisting power of nearly 50 per cent. There was another point with regard to dust: he had let The Rev. Mr. Whewell agreed with Mr. himself down a very steep inclined plane, and Russell in nearly all his remarks, which he when he attained a speed of 60 miles an hour, considered most valuable and important to he had a quantity of sand put on the rails, be considered. It was clearly ascertained and the consequence was, that the steam- that the greater the velocity the less the reengine came to a stop.

sistance. As to the second subject for discussion- Mr. Russell felt convinced that by adopting namely, “ On the application of our know- a considerable velocity, the Atlantic might ledge of the phenomena of waves with a easily be crossed with steam-vessels. view to the improvement of the navigation The Chairman (the Marquis of Northampof shallow rivers and canals.”

ton) said, that the observations of Mr. Rus.

power.

RESUSCITATED INVENTIONS.

365 sell were most important, and that the grati

RESUSCITATED INVENTIONS. tude of the country was due to him for his experiments.

Sir,-In a recent Number of The Repertory of Arts there is a copy of a spe

cification of a patent granted to Mr. IMPROVEMENT IN NAPIER'S RODS.

Booth for improvements in steam loco. (From Second Day's Proceedings.)

motive-carriages ; one of wbich in proveIn the section of mechanical science, Mr. Hawkins read a paper on an improvement

ments is the "application ofa throttle-valve

to the eduction-pipe of the cylinders.” upon Napier's rods, for facilitating the mul

The idea of this is not new ; one of the tiplication of high numbers with little liability of error, the invention of Mr. J. N.

early volumes of the Mechanics' MagaCopham, of Bristol.

zine contains an account of the applica. The invention consists in cutting each of tion of a throttle-valve to the eductionNapier's rods into cubes, and in stringing the pipe of a locomotive engine used on one cubes together by means of pins passing of the railroads at a northern colliery through two perforations in each cube, made several years before. The mere mention at right angles to each other parallel to the of this circumstance tends, in some meafigured sides.

sure, to show the increasing value of the By this arrangement the cubes may be

Mechanics' Magazine as a record of usereadily placed in such positions in respect to

ful and valuable inventions. each other that the product may be obtained by addition only, without the necessity of

The mode of traction through canal transcribing the figures from the rods previous

tunnels given in a recent Number of your to the addition, ibus' avoiding a great lia.

work (though displaying considerable bility to error, and effecting a saving of time ingenuity as regarding the arrangement in the calculation.

of some of the parts) is also not new. The pins are in two sets with heads of two In the year 1828, I was on board a siinidifferent shapes.

lar sort of boat, and passed in it through On the beads of one set of pins are marked the tunnel at Islington. The boat was 0. 1. 2. 3. 4. 5. 6. 7. 8. 9. respectively, the nearly of the width of the tunnel, and its same pin having the same number on each

sides were protected by guard-rails; the side of the head; but the number on one side of the head is inverted in respect to the

chain (of common construction) made

two or three turns round an iron roller, position of the number on the other side. The heads of the other set of pins are also

and passed in and out at head and stern numbered 0. 1. 2. 3. 4. 5. 6. 7. 8. 9., but the

of the boat through a wrought-iron tube. pin having 0. on one side of the head, has 9. Motion was given to the said roller by a on the other side ; that having 1. on one side,

having 1. on one side, high-pressure engine of 4-horse power, has 8. on the other, &c. The figures in this the cylinder of which was fixed in a hori. set, also, are inverted in respect to those of zontal position with the usual contrivance the opposite side of the head.

for reversing motion. This tunnel, about The cubes are kept strung on those pins

900 yards long, was traversed by this which have the same figures on each side of

boat, with two Thames barges in tow, in the head : 10 cubes on each pin representing about 15 minutes. Coke was chieflv one of Napier's rods.

used as fuel ; and it is worthy of remark, On the pin marked 0. all the cubes are

that at the head of the boat the heat and marked 0. on both sides. On the pin marked 1. the cubes are marked

sulphurous smell was intolerable, even 0. 1. 2. to 9. on one side, and 9. 8. to 0. on

for a few seconds. Placed at the stern, the other side. The numbers on the two however, no other inconvenience was sides of each cube, on being added together, felt than the rush of cold air. This boat, make 9.

I understand, not sufficiently remuneratOn the pin marked 2. the cubes are marked ing the owner, was soon after discon0.2. 4. 6., &c. on one side, and 18. 16., &c. tinued, and the old and dangerous meon the other side. The numbers on the two

thod again reverted to. The horses sides of each cube, on being added together, generally employed in towing the barges make 18.

might be shipped on board a spare boat And thus the numbers on the cubes of each

furnished with a roller and chain as above pin are all consecutive multiples of the numbers on the head of the pin; and the two

described, and their services would doubtnumbers on each cube on being added to

less be eligible in towing the barges. gether make the number on the head multi.

I plied by nine—the numbers ascending on one

am, Sir, yours, &c. side, and descending on the other.

1. ELLIOTT.

EXTRACTION OF THE CUBE ROOT SHORT

METHOD OF CALCULATING THE CON-
TENTS OF VESSELS.

366 SHORT METHOD OF CALCULATING THE CONTENTS OF VESSELS.

probability of obtaining the required root.

Having also a short time since been Sir,--In looking over some of the back applied to for a short method of finding volumes of your valuable miscellany, I

the content of eisters, &c., in gallons observed in pp. 330 and 331 of vol. xvi.

or bushels, by knowing the length, two methods of extracting the cube root,

breadth, and depth, I naturally turned to which I am somewhat surprised have not

your museum of information for the rea been noticed in some of the subsequent quired rule, where I soon discovered in Numbers, more especially as the former

the Number for January 19, 1828, a rule of the two methods (Mr. Laker's), in my apparently to the purpose ; which, howopinion, as well as in that of several of

ever, being calculated for Winchester my aequaintance, is of great practical bushels, was inapplicable to the case in utility, being very concise and also ap

point, and as no rule for finding the conplicable to every case that can oceur ;

ient in imperial measure has since ape but the latter method, communicated by peared, I take the liberty of offering the F. B., is impracticable, except in a very

following formula, the insertiop of which, few cases, and consequently useless. This

should you deem them worthy of a place is easily proved by taking the example

in your Magazine, will oblige, illustrating the first method, when F. B.

Yours, &c. would find himself involved in literally

J. L. an endless maze of figures without any Maidstone, Aug. 2, 1836.

Short Method of finding the Content of a Parallelopipedon in Imperial Measure. Let l = length, b = breadth, d=depth, all in feet, and e content.

8115d Then, if c be required in gallons

13 If c be required in bushels, the formula becomes

101 16 d

13 Example 1.-In a tank where 1 – 6 ft. 3 in., b = 3 st. 3 in., and d=4 ft., required:

81 x 6.25 X 3-25 X 4 the content in imperial gallons:

13

=5064 gallons, the content. Example 2.--Required the content in imperial bushels of a corn-bin, when l=8 steg

105 X 8 X 4 X 3 b=4 ft., and d=3 ft. :

13
744 bushels, the content.

101bd In some cases the readiest method for bushels will be found to be

13 nearly; then to every 10 bushels thus found add 1 gallon.

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MANUFACTURE OF BEET-ROOT SUGAR IN

RUSSIA. Şir',~ The manufacture of beet-root into sugar in the Russian empire has of late become very extensive; there are already no less than twenty-five large establishments for this purpose in different parts. Thinking that the following account of one of the principal of these establishments, viz. Micharlofsky Sugarworks in the governinent of Tula, the property of Count Bobrinsky, may be interesting to the English public, I send it for insertion in your widely circulated Journal ;

50

a

Produce of one pood of beet 2 lbs. of raw sugar at 1 ro. 10 co. per lb.

The number of men employed 250.

The quantity of land required to produce the beet 350 deciatines =915 acres.

The beet is generally taken from the

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