US760676A - Ribbon mechanism for type-writing machines. - Google Patents

Description

PATENTED' KEY 24. 1904.

0; E. YETMAN. N RIBBON MECHANISM FOR TYPE WRITING MACHINES.

APPLICATION FILED SEPT. 26,1900. RENEWED MAR. 18, 1904.

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'PATENTEIJJI M224, 1904'. 0-. E. YETMAN. I

RIBBON MECHANISM FOR TYPE WRITING MACHINES;

APPLICATION nun snrm. 26, 1900. unnwnn MAR. 18, 1904. I no MODEL. s sums-sunk:- 2.

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No. 760,676. PATENTED MAY 2.4, 1904.

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RIBBON MECHANISM FOR TYPE WRITING MACHINES. APPLIOATIONYIILED SBRT. 26, 1900. RENEWED MAR. 16, 1904.

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, PATBNTED AY"24,"1904.

, 0. B. YBTMAN. RIBBON MECHANISM FOR TYPE WRITING MACHINES APPLIOAIIOIN IiLE-D SEPT. 26, 1900. RENEWED MAB. 18, 1904 5 SHEETS-SHEET 4.

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kwallbrugyfl THE NORRIS rflzns 00.. PHOTO LlTHO-. wnsumwromp a PATENTED MAY 24, 1904.

0. E. YETMAN. RIBBON MECHANISM FOR TYPE WRITING MACHINES.

I rrmouron FILED SEPT. 26, 1960. RENEWED MAR. 18, 1904. '30 MODEL. 5 sums-sun 5x admbz l UNiITED [ST TES meme May 24, 1904. V

PATENT- O FICE;

f oIIARLnsnr TMAN, OF OAKPARK, ILLINOIS, ASSIGNOR TO WORLD FLASH COMPANY, OF CHIOAGO,, ILLINOIS, A CORPORATION.

'Rl BBON MECHANISM FOR TYPE-WRITING MACHINESQ SPECIFICATION forming part of Letters Patent No. 760,676, dated May 24, 1904.

application filed September 26, 1900. Renewed March 18, 1904. Serial No. 198,886. (No modeLl ,To all whm, it may concern:

Be it known that I, CHARLES E. YETMAN, a resident of Oakpark, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Ribbon Mechanism for Type-VVriting Machines, of which the following is a full, clear, and exact description.

This invention has relation more-particularly to that class of type-writingmachines commonly known 'as visiblejtype-writers; and the object of the invention is to provide improved construction of mechanism for controlling the position and feed of the ink-ribimpression upon the paper.

bon through which the type-bars make their,

provernent hereinafter described, illustrated in the accompanying drawings, and particularly pointed out in the claims at the end of this specification. J. I

Figure 1 -'s a view in vertical longitudinal section on line 1 1 of Fig. .3. Fig. 2 is a detail view on line 2 2 ofFig. 4. Fig. 3 is a front view in elevation of the rear part of the machine, parts being removed. Flg. 4 is a detail front view, upon an enlarged scale, of

.the ribbon plate or support and adjacent parts. Fig. 5 is a rear view of the parts. shown in Fig. 4:. Fig. 6 is a detail plan View of the ribbon-spools, their operating-shaft and adjacent parts; the frame ofthe machine being shown in horizontal'section. Fig. 7 is a-view in horizontal section through the shaft whereon the ribbon-spools are mo'untedg "Fig, 8 is a vlew 1n vertical section on "line 8 8 of Fig.

7. Fig.9 is a detail view in "longitudinal sec.- tion through the camrsleeve that is mounted on the ribbon-spool shaft. -,,Fig. 10 is a detail view in vertical section on;, 1ine' 10 1.0 of Fig. 4;. Fig. 11- is a detail viewpartly in elevation and partly in section,-showingthe: universal bar and its connections- Fig. 1 2 is a viewin vertical cross-section through one of theribf hon-spools and the shaft whereon it ismountf ed. Fig. 13 is a detail inner face view of the clutch-plate that is, attached to each.of .the ribbon-spools. Fig. 1a is a view in central vertical section through the clutch plate shown in. Fig. 13.

, tion.

Inasmuch as the present invention has relation simply to the mechanism for controlling the movements .of the inking-ribbon, I do not- Office of even date herewith,'bei ng Serial Nos. 1

31,198 and 31,199.

A designates the main frame of the machine, this frame being of any suitable construction. Across the main frame A extends I r a comb-bar B or other suitable support, upon The invention consists in .the features of im-' which willbe pivotally sustained, as aththe leversc of the space-bar C. By reference to Fig. 1- it will beseen that the levers c of the space-bar areprovided at their inner ends with upwardly and inwardly extending arms c, to which are connected springs 0 that serve 'to'hold the space-bar inthe normally raised position shown in Fig. 1. Between the side levers c of the space-bar is located the universal bar D '1), (seeFig. 1,) that is also pivotally connected, as at d, (seeFig. 11,) to the comb-bar B or other convenient support, the sides of the universal bar D D being shown as providedavith offset pins d,.adaptedto be engaged by the space-bar levers c as the spacebar is moved downwardly. It will be understood, ,of. course, that the usual key-levers (not shown) extend above the, space-bar and are pivoted at, their inner .end, so that the universal bar will be rocked each time that. a key-lever is depressed. The rear portion D of the universal bar extends upwardly at each side of the machine, and to these upper por- 'tions. D are pivotally connected, as. at d, the

links 2, the inner ends of these links being pivoted, as at.3, to crank-arms 4, that are fixed upona rock-shaft E. By reference to fFig. 3 it will be seen that the rock-shaft .E has its ends sustained by pointed pivot-screws 5, that extend inwardly from the sidewalls of v the main frame A. Tothe rock-shaft E is keyed a rock-arm e, the slotted upper end of which receives a spin-fi, that projects from the crank-arm 7 ,that is fixed to a short.

shaft 8, (see Figs. 1, 1, and 5,) journaled in the arms 9 of a hanger-plate 10, that is fastened to and depends below the front carriagerail F. This carriage-rail F and its companion rail F serve to support the carriage Gr, whereby the cylindrical platen G is sustained; but as the carriage mechanism forms no part of this invention it need not be more particularly described;

By reference to Figs. 4 and5 of the drawings it will be, seen that the rock-shaft 8rhas fixed thereto the rock-arms 12, through the lower ends of which pass the journal-screws 13, that are chambered to receive the ends of the shaft 14, whereon are revolubly mounted the ribbonrolls and 16. The shaft 14 passes through the lower ends of the guidebars or rods 17, to the upper ends of which bars is connected the rib' bon-guide plate or carrier H. By reference to Figs. 1 and 10 it will be seen that the upper ends of the bars or rods 17 pass through guidegrooves formed in the angular end portions of the guide-arms 18, that rise from the front of the carriage-rail F. The hanger-plate 10 is provided with depending arms 20,(see Figs.

2, 4, and 5,) in the lower ends of which is mounted a shaft 21, that carries the ribbon- -rolls 22 and 23.

The ribbon guide-plate or support H is shown as provided with a series of obliquelyarranged' slots h, it, if, and if, through which passes the ink-ribbon J. The slots k and h are preferably formed with openings it to permit the ready removal and replacement of thence forwardly and downwardly below the roller. 15, thence up through the slot If of the plate H, thence across the open space If of the plate, thence through the slots 71 it, and h of the plate, thence below the roller 16 and above theroller 23 to the companion ribbon-spool K.

From the construction of parts as thus far defined it will be seen that each time the spacebar 0 or one of the key-levers is depressed a corresponding depression will be given to the 7 front portion of the universal bar D, causing the upper portion D of this bar to rock forwardly. This forward movement of the upper part of the universal bar will draw forwardly the crank-arm 1 and turn the rock- 1 shaft E. The arm 0 of this rock-shaft by its engagement with the pin 6 will rock the crank 7 of the rock-shaft 8, thereby turning this shaft and causing its crank-arms 12 to swing forwardly and upwardly and in so doing'to raise the ribbon-plate H and the ribbon carried thereby. In Fig. 10 of the drawings the ribbon-plate is shown by full lines in its normal or idle position, and by dotted lines the parts are shown in the position that will be assumed when a key-lever or the space-bar has been depressed, as last described, and it will be seen that as the ribbon-plate H is thus lifted its upper end will be swung toward the platen Gr, so as to bring the inking-ribbon into proximity to the surface of the paper to be printed upon. As soon, however, as the spacebar or a key-lever is released the ribbon-plate H will drop to its normal position, thereby exposing to the view of the operator the printed line.

I am aware that a visible type writing machine'has been heretofore constructed in which the inking-ribbon has been carried by a pivoted support adapted to be swung upwardly and toward the platen at each depression of atype-lever or the space-bar, the ribbon support swinging forwardly and outwardly to normal position when the key-lever or space-bar was released; but in practice I have found that by providing the ribbon-s11 pport with means whereby it may be reciproeated at substantially right angles to the radius of the platen and in front of the printing-point a more effective exposure of the ribbon to the action of the type-bars is secured, the ribbon plate or support responding more quickly to the action of the key-levers and space-bars in'securing a full exposure of the printed line.

A shield or guard H is arranged in front of the ribbon-plate H. This shield or guard is provided with feet or extensions h bent at right angles to the plane of said shield and secured to the carriage-rail F by means of screws 71., passing through open-ended slots [L12 in said feet or extensions. The shield or guard is also provided with a pointer a, which serves to indicate the printing-point.

The inking-ribbon J is adapted to be wound first onto one and then onto the other of the ribbon-spools K and K, and the mechanism whereby the automatic winding of the ribbon is effected will next be described, it being understood, of course, that in this as in all similar type-writing machines the ribbon will be given a step-by-step movementcorresponding to the action of the escapement mechanism whereby the paper-carriage is controlled.

The side plates of each of the ribbon-spools K and K (see Figs. 6 and 7) are attached to the hubs in and are carried upon the ribbonspool shaft M, that is journaled in a suitable bracket 25 at one end, while its opposite end is supported by a suit-able bearing 26 in the side wall of the main frame. Upon the shaft M and within the hubs l; of the spools K I and K is a collar 28, secured to shaft M by screw 28, (see Figs. 7 and 12,) lengthwise of which 1s formed a slot 29, that receives a sliding pawl 30. This pawl 30 is formed wlth an offset arm 31, that extends through an opening '.shaft M.

. formed in the collar 28'into the slot m, that is formed lengthwise of the ribbon-spool shaft M. By reference to Fig. 7 .it will be seen that the arm-31 of the pawl 30 enters a notch '22 of a shifter-bar N, that lies within the groove on of the ribbon-spool shaft M, the notch 12,- however, being formed considerably larger than the arm 31 for the purpose to be presently the plate P, the, teeth of thisplatebeing alsoarranged in position to be engaged by the op- 20 posite end of the sliding pawl 30. Each of the ribbon-spools K and K is loosely mounted upon the shaftM and travels in unison therewith only when its corresponding ratchet or clutch plate P is engaged by the pawl 30. Hence it will be seen that the ribbon J will be wound on that spool the clutch ofwhich is in engagement with the 'pawl 30, that partakes of the revolution of the-ribbon-spool' shaft M. It will ,be understood, of course, that the shaft M will beldriven" by suitable gearing as fromthe escapement mechanism of the paper-carriage, this gearing engaging with the gear-wheel 35, that is loosely mounte ed upon the shaft M, but is connected therewith 'by a pawl 36, that engages a ratchet fwheel 37, the hub of which is fixed to the In order to automatically reversethe-direction of travel of the ribbon when it has been entirely wound from off one of the spools and onto the other, I provide theimproved mechanism next to be described.

Upon the shaft M is mounted the annular cam R, that is preferably sustained. within a sleeve R, to the interior of whichitis-fixed or in piece whcrewith'iit is formed; The annular cam R has a continuous'camgroove r of slnuous shape, 'onc-hailfof this groove being shown in Figqi= 9 of the drawings, it being understood thatij theoppositehalf is oflike shape. Withinthe .camgroove 0" extends a stud or friction roll n, that is fastened to the shifter-bar N, so that whenever the cam R has partial revolution imparted thereto a longitudinal shift of the bar N is effected, by the en gagement of the cam with the stud or roll 02..

i From the periphery of thecam sleeve R pro? -ject four teeth, two of these teeth, 9*, being arranged at diametrically opposite points at one end of. the sleeve R, whilethe other two teeth, 1*, are similarly arranged at the opposite end ofthe sleeve," the teeth r and r how- I ever, being disposed at-right angles to each other upon the surface of. the sleeve. (See Fig. '6.)

Fixed to the shaft Mat the jends of. thecam R are the releasing-plates S and S these plates i being provided, respectively, with'the extensions s and s of a height equal to or slightly greater than the height of theteeth 1 and 07 The teethr and r are adapted to be engaged,

respectively, by the shifter-pawls T-and T,

that are journaled upon a shaft or support 40 at the back of the main frame A. (See Fig. 6.) The pawl Tis rigidly connected by a suitable sleeve that is mounted upon the shaft40 with its companion controlling-pawl If, and the pawl T is connected to its companion controlling- .pawl t.

The controlling-pawl t is adapted to rest upon the surface of the ribbon woundupon the spool K, while the controlling-pawl t bears upon the ribbon that is woundupon the spool K. The.controllingpawls t and t are so disposed with relation to their respective shifter-pawls T and T that when the ribbon' is about exhausted from one of the spools-for example, the spool Kthe corresponding controlling-pawl a will at-such time be adjacent the hub of the spool K and will" permit the free end of the shifter-pawl T to descend into such position-that it willcontact with the tooth a" (see Fig.6) of the cam-sleeve R. This contact of the pawl T with the tooth rwill detain the cam-sleeve and cam R, while the shaft M continues to revolve. As'soon, however,as the inclined extension sv of the .95 guard S passes beneath the free end of the shifter-pawl T it will lift the pawl from engagement" with'the tooth r, after which the cam-sleeve R will continue to revolve with the shaft and in its protected position at the side of the guard lug or extension .9, and manifestly so long as the tooth 1"" is in this position gagement of'the pawl T'with the tooth'r will detainzthe cam-sleeve R and cam R during a quarter-revolution of the shaftM. If, there fore,it*be assumed that the stud or roller n .be in one of the portions of the cam-groove o 1 it cannotybe struck by the pawl T. The ennearest the right-hand releasing-plate S, then as the sleeve R and cam R are detained by by pawl T while the shaft M and'the bar N make aquarter-rrvolution the stud or roller n on the bar N will move along the cam-groove r'intothat part ofthe-groove nearest the lefthand releasing-plate S and in'so doing-will impart a corresponding longitudinal move ment to theshifter-bar N. During this ini-' tial movement of the shifter-bar the arm 31 of the pawl 30 (see Fig. 7)-w ill not be afl"ect ed,-because the slot n of the shifter-bar is considerably larger than the arm 311' As soon,

however, as the shifte'r-bar N is moved toward the left (see Fig; 7) a suificient distance .to cause the points of the V-shaped cam-lugs n to pass slightly beyond the spring pressed rolls N these rolls bearing upon the opposite inclined sides ofthe lugs n will cause the shifter-bar to move quickly toward the left and in so doing the bar by its contact with the arm 31 will cause the pawl 'to pass from engagement with the annular teeth of the clutch-plate P of the spool K and into engagement with the teeth of the clutch-plate P of the spool K. Hence the spool K will partake of the travel of the shaft M and will cause the ribbon to be wound onto such spool and from off the spool K. The spring-arms a, by

which the rollers N are carried, are simple plate-springs that are conveniently held by a collar at one side of the gear-wheel 35.

The end of the spool-shaft which projects outside of the main casing is shown as provided with a crank-handle M whereby the shaft may be turned by hand when it is desired to replace the ribbon or for any other purpose.

I am aware that a type-writing machine has been heretofore constructed in which each of the ribbon-spools has been provided at its outer face with a cam and in which the spoolshaft has been provided with a shifter-bar having two separate lugs or arms that engage the individual cams of the ribbon-spools and cause the pawl to be shifted in order to throw either of the. spools into or out of clutch engagement with the spool-shaft. By my present invention however, a single cam is caused to effect in much more satisfactory manner the function of the two cams in such prior construction, and the danger of a dead-locking of the shifter-bar against the cams is avoided.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. In a type-writing machine, the combination with a platen, of a shifting, rigid 'ribbon-support having slots through which the ribbon passes,oppositely-disposed fixed guides for the opposite edges of said support, each of said guides having a combined sliding and swiveled connection at one point only with the edge of said support and an operating rock-arm pivoted directly to the end of said rigid ribbon-support, said rock-arm shifting said ribbon-support through said guides with a combined sliding and oscillating movement whereby said support, during its forward shift, is moved first tangentially and then radially toward the platen and, during its return movement, is moved first radially and then tangentially away from the platen.

2. In a type-writer machine, the combination with a platen, of a ribbon-support movable tangentially and radially toward said platen, said support having means for holdingthe used portion of the ribbon parallel to the line of print and for holding the unused portion at right angles thereto, fixed guides embracing opposite edges of said support intermediate its ends and operating means for said support comprising a rock-arm pivoted thereto.

3. In a front-strike type-writing machine, the combination with a platen, of a vertically shiftable ribbon-support having means for holding the used portion of the ribbon parallel to the line of print and for holding the unused portion at right angles thereto, means for guidingsaid supportintermediate its ends, an operating rock-arm pivoted to thelowel' end of said support and a movable guide for the ribbon carried adjacent the free end of said rock-arm.

4. In a front-strike type-writing machine, the combination with a platen, of a verticallyshiftable ribbon-support having means for holding the used portion of the ribbon parallel to the line of print and for holding the unused portion at right angles thereto, means for guiding said support intermediate its ends, a pair of operating rock-arms pivoted to the lower end of said support, movable guides for the ribbon carried between the free ends of said rock-arms and fixed guides therefor arranged adjacent the opposite ends of said rock-arms.

5. In a type-writing machine, the combination with a platen, of a ribbon-support comprising a plate H having a cut-:uvay space lt adapted to come opposite the printing-point and having obliquely-arranged slots In, W, h and 72/" through which the ribbon will be passed.

6. In a type-writing machine, the combination of the shiftable rib!)on-supportll having a cut-away space 717", and having the oppositelyarranged diagonal slots [1. lei and the parallel diagonal slots 71/, 71 through which slots the ribbon will be passed and the pair of adjacent ribbon-spools K, K upon which the ribbon is alternately wound and unwound.

7. In atype-writing machine, the combination of the shiftable ribbon-support H having a cut-away space/12", and havin g the oppositelyarranged diagonal lots W, 71/" and the parallel diagonal slots /1 71/, through which slots the ribbon will be passed, the (uplicate pairs of ribbon-guide rolls 15, 16 and 21, 22 and the pair of adjacent ribbon-spools h, Ii upon which the ribbon s alternately wound and unwound.

8. In a wpe-writing machine, the combination with a platen, of a ribbon-sup port, arms connected to said ribbon-support, guides for said arms, a rock-shaft and rock-arms for shifting said ribbon-support, a rock-shaft and cranks for actuating said rock-arms and a universal bar suitably connected with said cranks.

9. In a type-writing machine, the combination with a platen, of a ribbon-support provided with suitable slots or openings through which the ribbon will be passed, two pairs of ribbon-rollers mounted below said ribbonsupport and around which the ribbon will be passed, and means for lifting said ribbonsupport and one pair of said ribbon-rollers in order to bring the ribbon opposite and near the printing-point of the platen.

10. In atype-writing1nachine,the combination with a platen, of a ribbon-support, a pair ofstationary ribbon-rollersbelow said ribbon-support, a pair of movable ribbon-rollers 1 also arranged below said ribbon-support, and

suitable rock-shafts and cranks for raising and lowering said movable ribbon-rollers and said ribbon-support.

11. In atype-writing machine, the combination with a platen, of a ribbon supportand.

means for shifting-said ribbon-support at substantially right angles to the radius of the platen, comprising cranks and rock-shafts suitably connected to said ribbonesupport,

and a universal bar having upwardly-extending arms suitably connected with and rock-shafts.

12. Inatype-writingmachine,the combinasaid 'cranks tion with two ribbon-spools provided with individual' clutches and with-the spool-shaft, of-

a clutch-pawl and a single cam and shifter-bar for throwing said clutch-pawl intoand out of.

engagement with either of-said clutches.

13. In atype-writing machine, the combination with a pair of ribbon-spools and with operating means therefor, of clutch mechanism for alternately throwing said ribbon-spools into-and out of engagement with said operating means and a single cam and shifter-bar for shifting said clutch mechanism.

14. In atype-writing machine, the combination with a pair of ribbon-spools and with operating means therefor, of clutch mechanism for alternately throwing said ribbon-spools into and out of engagement with said operat ing means, a single cam and shifter-bar for shifting said clutch mechanism and means for locking the same in its shifted positions.

15.. In atype-writing machine, the combination with a pair of ribbon-spools and with opcrating means therefor, of clutch mechanism for alternately throwing said ribbon-spools into and out of engagement with said operating means, a single cam and shifter-bar for shifting said clutch mechanism, means for locking the same inits shifted positions comprising a V -shaped cam mounted on said shifter-bar and a cooperating spring.

' 16. In a type-writing machine, the combination with a pair of ribbon-spools and with operating means therefor, of clutch mechanism for alternately throwing said ribbon-spools .into and out of engagement with said operating means, a rotatable shifter-bar, a cam having a continuous cam-face normally rotatable with said bar and cooperating therewith for shifting said 'clutch mechanism, means for holding said cam stationary, and means for releasmg sald cam.

17. In a type-writing machine, the combina' tion with a pair of ribbon-spools and with an operating-shaft therefor, of clutch mechanism for alternately throwing said spools into and out of engagement with said shaft, a shifter- I bar rotatable with said shaft, a cam having a continuous cam-face normally rotatable with said shaft and cooperating with said shifterbar for shifting said clutch mechanism, means for holding. said cam stationary andmeans for releasing said cam.

1 8. In a type-writing machine, the combination with a pair'of ribbon-spools and with operating means therefor, of clutch mechanism for alternatelythrowing said spools into and out of engagement with said operating means,

.clutch mechanism, ratchet-teeth on said cam,

shifter-pawls engaging said teeth, and controlling-pawls operatively connected to said shifter-pawls and bearing upon the ribbon on the spools.

20. In atype-writing machine, the combination with two ribbon-spools having individual clutches and with a pawl for engaging said clutches, of a single cam arranged atone side of said ribbon-spools and upon the spool-shaft,

a single cam forv shifting said clutch mechan a clutch-bar passing through said cam and provided with a stud or offset that engages the slot of said cam, suitable teeth upon said IOO cam, releasing-plates fixed to the spool-shaft.

adjacent said teeth,'individual shifter-pawls for engaging said teeth of the cam and controlling-pawls connected to said shifter-pawls and bearing upon the ribbon on the spools.

, 21. In a type-writing machine, the'combination with two ribbon-spools and with a spoolshaft, of a cam loosely mounted upon said shaft and having a continuous cam-shaped slot extending around said shaft, individual clutch mechanism whereby either of said spools may be engaged with the spool-shaft, a shifter-bar for actuating said clutch mechanism provided with a stud or extension within said cam-slot, suitable teeth projecting from said cam and whereby its movement may be temporarily arrested, shifter-pawls for engagings'aid teeth, releasing-plates mounted upon the spool-shaft for disengaging said shifter-pawls from said teeth and suitable controlling-pawls connected with said shifter-pawls and bearing upon the ribbon on the spools.

22. In a type-writing machine, thecombination with two ribbon-spools and with a spoolshaft, of individual clutch mechanism where- .by either of said spools may be caused to revolve with said shaft, a cam mounted upon said shaft at one side of said spool and provided with a continuous cam-surface and with teeth at its opposite ends, releasing-plates at theopposite ends of said cam adjacent said teeth, shifter-pawls adapted to engage the teeth at the opposite ends of said cam and controlling-pawls connected with said shifterpawls and bearing on the ribbon upon the spool.

23. Ina type-writing machine, the combination with a platen, of a ribbon-support, a stationary shield H substantially covering said ribbon-support and provided with ofiset feet 70 78 by which it is secured in place, and means for shifting said ribbon-support.

24. In a front-strike type-writer machine, the combination with a platen, of a vertical shiftable ribbon-support, a vertical shield fixed in position and substantially covering said ribbon-support when in normal position,

a printing-point indicator mounted on said shield and means for shifting said ribbon-support behind said shield and between said platen and the printing-point indicator.

25. A type-writing machine, the combination with a pair of ribbon-spools and with operating means therefor, of clani 'iing mechanism for alternately throwing said spools into and out of engagement with said operating means, a single rotatable cam having a continuous cam-face and means operated thereby for shifting said clamping mechanism when the ribbon is unwound from either spool.

CHARLES E. YETMAN.

Witnesses:

ARNIGII D. RIoIIARnsoN, M. 1. W ILFERT.

Images