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THE

Scots Magazine,

AND

EDINBURGH LITERARY MISCELLANY,

For FEBRUARY 1815.

Description of a PATENT PRINTING PRESS, invented by JOHN RUTHVEN, Printer, Edinburgh.

WE bave departed, this month, from

the usual plan of our frontispiece, in order to illustrate an elegant and ingenious invention, which promises to be of the greatest advantage to the Art of Printing, and thus to promote the interests of literature in general. It applies to that part of the process which consists in taking off the impression, well known to be the most laboricus, and, at the same time, one on which good printing most essentially depends.

Before entering into a description of this invention, it may not be improper to give a sketch of the construction of the Common Printing Press, with a brief account of the improvements that have been attempted to be made on it, in order to shew that there is occasion for one on new principles and an improved plan. For many may probably conceive, that the Presses at present in use, are sufficiently adapted for the purpose, else they would not have continued for such a series of years, even of centuries, without attracting the attention of the ingenious; for it is a fact, that on comparing representations of the oldest Presses, we find that both the principles and construction are nearly the same with those of the present day!

It appears that the screw was carly

applied in the Printing Press for producing pressure; and that the construction of all Presses has had the types placed on a moveable carriage, where, after being inked, they were passed under the surface for pressing, and then returned. It is remarkable, that this latter mode of moving the form of types under the pressing surface, has been uniformly adopted in all alterations or improvements that have been otherwise made: it has thus been always impossible to increase the lever, which turns the screw, being power, from the radius of the simple confined. It is evident that this al lowed but a limited surface, not larger indeed than one half of a large sheet, to be pressed at one descent of the screw. The difficulty seems to have been insurmountable; for the same construction still continues to be followed in the common Printing Press. The limitation of surface must always have proved a serious evil for various works, particularly duodecimo, because the pressure necessarily came tu icon the center pages of every sheet, while the other parts of the types received the pressure only once.

Besides other disadvantages, the following may be briefly stated: 1st, The difficulty of ascertaining when a proper degree of pressure was given. 2d, The irregular manner of puiting the lever, whereby the sume sheet received very different degrees of pressure. 3d, The manual labour, and bodi y exer

tion, which is not only excessive, but attended with fatal consequences to the initiating workman, as the shocks which the breast sustains in pulling the lever, frequently produce pulmonary ailments. 4th, The nice attention and accuracy requisite in having the types exactly under the center of the pressing surface before bringing it down. 5th, The same operation being necessary for the smallest card, as for a whole sheet: and the necessity of placing smail work always on the same part, thus wearing that part sooner out, and making it defective for executing larger work.

These defects appear to have attracted the attention of the French, since a Press bearing their name has been long known. The principal object attained by this Press is, that the whole surface of the sheet is printed by one exertion; but the means adopted to produce this effect, prove, that the advantage gained in power, is overbalanced by the time lost in motion, before the impression is given, which has consequently prevented its being generally used. The most important improvement, however, was brought forward some years ago, by the present Earl Stanhope, under the name of the Stanhope Press: this Press differed from others, by being made wholly of iron, and, by the introduction of a crank, attached to the lever, for taking down the upper surface, and pressing it on the types,~ thas affording a command of power sufficient for printing the surface of a sheet. The principal objection to this method is, the immense force exerted against the upper part of the frame that confines the pressure; as it has been found that, by the introduction of an additional sheet or two of paper, and the workman then drawing the lever, till the periphery of the crank came in a line with the fulcrum, the Press could be instantly broken.

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With these considerations in view, the present undertaking was commen

ced. Having ascertained, by experiment, the immense advantage of the lever over the screw, by removing the friction, it became only necessary to discover how a parallel motion could be procured from an angular action. This was gained, by making use of two levers of the second kind, having their fulcra, or props, at opposite ends, and joining both levers in the center; and receiving their motion from a crank. The construction was then commenced, 1st, By having a stationary tablet for the types: 2d, By placing the levers in two metal cheeks, or frame, and attaching them to the under surface of the tablet: 3d, By making the platen, or pressing surface, sufficiently large to cover the whole sheet; and fixing a strong har of metal along the upper side of it, making each end rest on two wheels, or rollers, for carrying the platen on two rail-rods, placed parallel with each end of the tablet, and projecting sufficiently over to allow the platen to stand clear of the types, and the sheet of paper to be placed on them in the usual way. After the types are inked and the paper put on them, the platen is drawn over, and unites at each end with the levers under the tablet, which is then so forcibly, but at same time so easily drawn down, by means of turning a handle about one-fourth of a circle, which actuates a crank, that the impression on the whole sheet is produced at once, and with extremely little exertion to the workman.

Farther, the advantages resulting from adopting Printing Presses constructed on these principles, may be briefly stated as follows: 1st, The types remain stationary: 2d, The platen, or pressing surface, is the size of the whole sheet: 3d, A saving of time is gained by the platen being brought on from the side: 4th, By a regulator attached to the handle, any requisite degree of pressure may be correctly given: 5th, The platen being taken down at each end, and the resistance

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sustained against the under surface of the tablet, affords the most complete security to all the parts: 6th, The large Press will take off an impression from a small piece of work, although placed at one end, and without requiring any block to bear up the other; of course, it is not necessary, in this Press, to place the form of types in the center of it: 7th, The two surfaces being pressed together without any connection with the frame of the press, it requires no levelling, or staying; and a Press for a demy or royal sheet, occupies only about four cubic feet! 8th, The accustomed motions of the experienced Pressman are so completely retained in this invention, as to enable him, in the course of one or two hour's practice, to work with equal facility as at the common Press: 9th, The principles and construction are equally applicable for Presses not larger than one cubic foot; and which are capable of printing off an octavo or quarto page, with greater celerity than a large Press; and may be worked on a table, without being fixed. This not only relieves the large Press from doing such work as tends to injure it; but will also furnish an interesting amusement to such as desire to become acquainted with the useful Art of Printing.

Another important use, for which these Presses have been found equally well adapted as the excellent machines of the ingenious Messrs Watt and Bolton, has been discovered by MR D. BRIDGES, jun. of Edinburgh, who has applied them for Copying Letters, of which a dozen may be copied at once; so that they serve both as a Printing Press and Letter-Copying Machine.

Although it cannot be attempted to point out the many useful purposes which this invention embraces, it must appear evident, that the introduction of the Portable Press into the ARMY or NAVY would prove highly advantageous; the correctness and expedi

tion with which orders might be distributed, exclusive of executing various other necessary regulations that require to be printed, will certainly render them extremely desirable appendages to every regiment, or vessel of war. In Public Offices and Banking Houses their utility would soon be discovered.

It is also expected that this Press, on account of the very large surfaces it is capable of printing, will be found admirably adapted for Calico-printers,

for one block of the whole breadth of the cloth may be impressed at once; and thus a multiplicity of operations be saved, besides the work being performed with greater accuracy and elegance.

In conclusion, it may be added, that this invention has been produced after upwards of twenty years of practical and constant experience in the printing business; and that a Specification of the Patent, with drawings of the machinery, will be found in the Repertory of Arts for September 1814.

The Presses are manufactured for England, by Mr KEIR, Engineer, Camden Town, St Pancras, London, whose abilities are already well known to Printers. They are also made by MR ANDERSON, Leith Walk Foundry, Edinburgh, under the immediate superintendance of the Inventor; and as they are always ready for delivery, an opportunity is given of previously inspecting them.

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References to the Plate.

Fig. 1 is a horizontal plan of a printing press; Fig. 2 a vertical section taken through the middle; Fig. 3 an end view; and Fig. 4 a perspective view; the same letters of reference being used in every one. A A represent the tablet or surface upon which the types, &c. are laid. This tablet is mounted upon a frame of wood, or metal, consisting of legs, B B, and

Cross

Description of Ruthven's Patent Printing Press.
the point

rod K, which acting upon
H of the lever G H I, moves it upon
its center G, and depresses the point
I, which being connected with the
extremities E of the levers D E, by
the link a, they are made to partake
of its motion, and draw down the pla-
ten upon the types by the clutches. FF
and hooks dd. By returning the
winch N to its original position, the
pressure is relieved, and the platen re-
moved from the types thus: at the
ends of the bar P two springs, e e,
Figs. 1 and 3, are fixed; and in the
ends of these, rollers or wheels marked
f, are fitted to revolve freely upon their
center pins. These wheels, having
shaip
grooves in their edges, run upon
angles, formed upon the upper edge of
two rails R R, which are extended
press, and pro-
across, the frame of the
ject sufficiently behind, as in Figs. 1
and 3. Upon these bars and wheels
the platen will run freely, to remove
it backwards off the types, but when
brought over them, the bolts dd will
enter the clutches F F, ready to re-
ceive the action of the levers, and
give the pressure upon the tympan.
give the pressure upon

To draw the platen forward over the types, a handle h is fixed upon it for the pressman to take hold by.

To make all the work compact, the centres D D of the great levers, and of the lower lever G, as well as the pivots L of the winch N, are all supported in one frame, composed of two metal cheeks S S, which are situated beneath the table, and united thereto by screws, or otherwise, as shewn by the dotted lines in the plan Fig. 1.

85

cross braces, C C; or any other kind of support may be used which will firmly sustain the tablet at a proper height from the ground, (as in fig. 4.) The tablet has the tympan 8 and 9 jointed to it at the end 9, in the usual and into the position of the dotted lines 10, to take off or put on the sheet of paper, which is confined by the frisket 11, in the usual man

manner,

open

ner.

For fastening the types upon the tablet, or what printers call making register, are screws, 13, 13, fitted through pieces which are made fast to the sides of the tablet; and between the points of these screws the chase, or frame of types, is held steady upon the tablet, and may be adjusted. Beneath the tablet are the levers marked DE DE, their fulcrums, or fixed center pins, being at D, and the act upon double hooks, or clutches, F F. When the ends E are depressed by means of the third lever I G, situated beneath and common to both, the connection being made by the link a, the fulcrum of the lever is at G; and H is a third point to which the power to actuate it is applied by a connecting rod K, the opposite end of which is jointed to a crank or short lever L M, situated upon an axis or spindle L, which extends to the front of the machine, and has a winch or handle N, Fig. 1, upon it, for the pressman' to turn it by.

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The platen of the press is shewn at OO on the top of the platen is a strong metal bar P, united to it by screws, at rr: at its extremities it has bolts, dd, fixed to it by screws, and at their lower ends they have heads, which are exactly fitted to the clutches, or double hooks, F F, before described. By means of these the platen is connected with the lever D E DF, so that a pressure may be produced when the wandle N is turned in the direction shewn by the arrow in Fig. 2. This, by turning the lever M about its center L, pushes the

upon

The power of the press will depend upon the proportions of the different levers, and the relation between the space described by the motion of the handle N, and the descent of the platen 0; but it should be observed, of this power press increases that the as the handle descends to the horizontal position shewn in Figure 2: for when the pressman first takes

hold

hold of the handle N, it acts but with little advantage in respect to power upon the levers, and therefore brings the platen down very quickly upon the tympans, with little loss of time or motion, till they have assumed positions, in which they exert more powerful action upon each other, as above stated; and this action continues to increase until the lever L M and rod K come nearly into a line, when the power is immensely great, and capable of producing any required pressure. The handle N is made to come to a stop, or rest, which vents its moving farther than the position of the dotted lines, and therefore regulates the degree of pressure given upon the work. But to give the means of increasing or diminishing the pressure at pleasure for different kinds of work, the end of the rod K is screwed into a box, or nut, therefore by turning it out or in, it has the same effect as leathening or shortening the rod, which produces a greater or lesser descent of the platen when the handle is brought to its stop.

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Another method of producing the same effect is to adjust the nuts which are fitted on the screws at the top of the bolts dd; or it may be done by loosening the screws at r, and fitting packing between the fitting of the platen and the bar P: the same may be done to adjust the platen parallel, if it prints more at one part than another.

If it is thought objectionable for the rod K to push endways on the levers, or the handle to go over, it may be made to draw or pull, by placing the lever M above the spindle L instead of beneath it, and also reversing the form of the lever G HI; the points G and H to remain as they are, but the point I to be on the opposite side of the center, viz. above it; and with this alteration the drawing of the rod K will produce the pressure, instead of pushing it, as in the figure.

DR HAMEL on the Art of making
Coffee

TO THE EDITOR.

SIR,

HAPPENING, the other day, to look over some Numbers of the Monthly Magazine, I met, in the one for Feb. last, with the following query:

"We hear much of the luxurious

beverage of coffee on the continent,

but I do not remember to have seen any of the practicable modes of making it in the works of travellers or others. Perhaps some of your readers will so far oblige another reader."

Not being acquainted with the Editor of the Monthly Magazine, I take the liberty of communicating to you, for insertion in your work, the following observations on this subject, hoping that they may reach the author of the above question, and may prove interesting to readers in general.

When travelling on the continent about two years ago, I met with a gentleman, just returned from Vienna, who had brought with him a new apparatus for making coffee, which had been then but lately introduced there, and which pleased very much every one who saw it. This apparatus consists of a glass phial, to which a wooden handle is attached by means of two metallic hoops, from the lower of which three feet project downwards, on which it rests in an upright position. It is placed on a cylindrical metallic supporter, having its sides, perforated for the purpose of ornament, and one large opening, for introducing a spirit lamp, the flame of which acts on the under part of the phial. To illustrate this description, I send you a rough sketch of the apparatus. It is used in the following manner: After the ground coffee is put into the glass, boiling water is poured over it up to the neck, or to the place where the upper hoop is adapted, and the phial is placed over the flame of the lamp. When the fluid begins to boil

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