US755A

US755A - Sawmill-dog

Info

Publication number: US755A
Authority: US
Publication date: 1838-05-30
Anticipated expiration: 1855-05-30

Description

HEZEKIAH 'rHURBiiR, or PAINTED ros'r, NEW YORK.

sAWMILL-DOG.

Specificationof Letters Patent No. 755, dated May 30, 1838.

T0 all whom t may concern.-

Be it known that I, HEZEKIAH THURBER, of Painted Post, in the county o-f Steuben and State of New York, haveinvented an improvement in the construction of sawmilldogs, head and tail blocks of the sawmillcarriage, and especially in the inode ofusing the dogs and the means or apparatus by which they are moved, used, and applied;`

and I do hereby declare that the following is a full and exact description of my invention,

reference being had to the annexed draw 2In order to describe my invention, and explain its operation intelligibly, so that others skilled in the art may be able to make and use it, I describe other parts not claimed herein as my invention, but connected with it in the construction and arrangement of the parts, and in the use and` operation of my invention, and after that distinguish and dene more particularly what I claim as` my invention. l

First. IV construct the principal frame of the carriage in the common form of saw-mill carriages.

Second. The head block (A, Figures 1 and 2 and 3 in the drawings hereto annexed) movable on the carriage, as in the common construction,so as to be adapted to the length of the log, is about 22 to 24 inches wide, and 9 inches thick. The upper and inner corner or edge of the head-block (a) is rabbeted off 5 inches, by l inches deep, the who-le length of the block, to receive the log, and hold it from slipping or moving lengthwise, after it is rolled onto the carriage. The lower or horizontal part of the rabbet is lined with band iron, or other metal plate -linch thick 5 inches wide, made fast with screws; and

the perpendicular side of the rabbet is also lined in the .same manner, to prevent the log wearing the block, and on and against which iron or other metal plates the log easily slides and moves. The `band iron or plates here described, and also the other plates and castingshereafter described which are fastened on the top of the head block, are separated at the middle, that is, consist of two parts, a space being left between them at the middle of the head block, V inches wide, to give suliicient room and space for the saw when the carriage is gigged back, the saw, Ain that situation of the carriage, standing back its entire width in the head block at (Z9), Fig. 1Q. `A plateor band iron E, Figs. 2 and 3 inch thick, 2 inches wide, 2 feet long, extending from the. end of the head block next the logway, to the division before described for the reception of the saw, is screwed or riveted on the topof the Y head block next the rabbet before described, the edge being in the line of and coming in c ontact with the top of the perpendicular lining of the rabbet. This plate is for the purpose of forming with the casting next described, a horizontal groove for the dogslide hereafter described. An iron casting (c Figs. l, 2, 3)- `inch thick of the same length as the plate of band irondescribed, placed in the same position to the head block, is fastened to the headblockby bolts or screws passing through it, and through the said iron plate into the head block.' One edge of this casting consequently corresponds exactly with the perpendicular line of the before described rabbet. This casting is 2 inches `wide at the top by l inches at the bottom, the upper half projecting inch over the lower half on the side from the rabbet, so asV to make a horizontal groove the whole length of the casting #le by i inch, in whichthe slide (d) moves as here! after described. A slide (d Figs. l and 3) to which the dog is attached, is of'castiron 2O inches long inches wide at the top, 4 inches wide at the bottom, the lower half projecting inch, on each side, V-so as to fit snugly into the horizontal groove before described o-n theside next the rabbet, and

o-n the other side into another groove made f in precisely the same manner, by a plate F and lasting (e Figs. l and 3) of the saine dimensions as the one first described, and fitted and `fastened in the saine manner. The slide, CZ is ofthe same thickness as the castings. The'slide is cast, with a projection G Fig. 3 on the under side of the slide, one

inch, by T1- inch in width, in the middle, and extending the whole length of the slide. j This ioo projection of the slide downwardffts into `f groove turned up at the end nextthe saw;

the slide passing over this strip of iron till it comes to the end turned up, is stopped and held by it.

The dog (f) which is a half-bail dog, is

attached to the slide by means of ears which Y are raised on the slide toward the inner end thereof, that is, toward the end of the slide next the saw, and which are cast with the slide. The deg is lof wrought iron, and moves with the slide, being attached to it as above described.

(c c) a plate of cast ironV a inches Wide l Yto 1g; inches thick and the same length with the dog-slide, is riveted on the top of the clog-slide, projecting over the slide on the sidey toward the head of the head-block, or side from the log when placed on the carriage, about half the width of the said cast iron plate. This plate is cast with cogs or notches (g) an inch deep, and one inch wide,

on the projecting side of the said plate. .TheY

said plate is not flat, but the side or edge in which the cogs or notches are cast is raised so as to make an angle of about 20 degrees with the plane of the slide. The cogs and notches are cast for the purpose of receiving the end of the mill bar, which is used as a lever to move the dog slide, and with it the log when Y the log is dogged.

Arblock or plank la Figs. 1 and 3 2 inches thick, saine length with the castings, and of Vsufficientv width to extend from the castings to the outside of the head block, is pinned Von the top of the head block between the castings and the outside ofthe head block, that is, the side toward the head of the mill. The corner or edge next the castings is worked o to the saine thickness with the castings. Two iron pins L are set in this upper plank or block 3 inches from the cogs, and at convenient distanceY apart, and are used as fulcra, against which the mill bar rests in moving the slide as before described. These pins should rise about three inches from the block and are linches in diameter.

A screw bolt (71.) 1iinches diameter at the head passes through the head block horizontally from the outer side of theV head block, about midway of the castings before described, or 14; inches from the end of the head block next the log-way. This screw bolt passes Yin a groove cut horizontally across the head block and of a depth nearly equal to the diameter of the said screw-bolt, and is held down in the groove by thevplank or block which is pinned on the top lof the head block as before described, which block or plank is also slightly groo-ved so as to fit snugly over the saidvscrew bolt. A nut is placed vertically between the vhead block and the said plank or block which is fastened on it in such position corresponding withthe said groove that the screw bolt passes through it and is held by it. The screw is cuton the bolt only in that part which passes through the nut. The end of `the said screw bolt as will be perceived from screw bolt is made eight square orround and perforated for a lever-bar.

A. lever bar (i) of wrought or cast iron 15 inches long 1 inchdiameter, with an eye corresponding to the head of the bolt, fits tightly on the head of the said screw bolt. The extreme end or head of the said screw bolt is cut a screw, and receives a nut for the purpose of holding the lever bar fast on the screw bolt as before described. At the distance of about half the length of the said lever bar, on each side of the saidscrew bolt and in a horizontal line with the said screwv bolt, in the outer edge or sideof the head block are iron bolts or pins standing out about 3 inches lfrom the headblock on which the lever bar' restsrwhen turned do-wnV toward one or the otherend of the head block as the case may be, thatV is, according as the screwbolt is turned to press up against the projection in the slit or loosened from it, as the case may be. Y y

The other end ofthe head block is construc-ted and described as follows: fron castings of the saine form and dimensions in every respect, except length (which is 16 inches) and inthe same position in respect to the saw and the ratchet in the head block1 as the castings before described for the other end of the head block, and are placed upon plates for the purposeof forming horizontal grooves as before, are fas-V tened to this end of the head block. These castings are in line with the others. A slide is adapted to the grooves in the same manner as beforeV described, and of the same form, except that there is no projection on the under or lower side, and the length is only 12 inches. .A half bail dog which is also called a gage dog (KV) is attached to this slide in the same manner as before described. 7

The slide ss carrying the gage dog K just mentioned is held at any point desired, raccording to the thickness of plank to be sawed, by means of a screwl passingV horiy zontallythrough the head block in the same manner as the screw vbolt ybefore described and is likewise turned by a lever or pressing against a downward projectionfrom the slide it presses against a vertical plate m placed between the edge of the slide and end of the screw, a inortise being made in the casting forming thegroove of the slide to admit said plate to play freely, and said plate extending down into the block. Y p

A wooden lever (o) 2 feet long, rests upon the head block. The hand-end of the lever comes outv even with'the end of the head block. A wooden pin (00) l-l; inches in diameter, fastened perpendicularly in the headblock, one foot 'from the end of the headblock, and 8 inches from the outer edge o-r side of the head block,and rising 4 inches from the headblock.v is Vthe fulcrum on which the lever moves and to which the lever is held, the pin passing through the leve-r by an auger hole in it. A' inch pin (79p) passes through the top of the perpendicular or fulcrum pin to keep the lever fro-m coming off.v The lever is so shaped or fashioned that the hand end and center where the fulcrum pin passes through it is about 2 inches thick, and the other end 4 inches.` In the top, and as near the end last mentioned as may be a staple is driven (the shanks of the staple standing in a line transverse to the line of the lever, and so that the staple will be open toward the hand end of the lever). A staple is also placed in the bow-leg of the gage dog, about 3 inches above the ear. This staple is connected with the staple in the end of the lever last described by an iron link M Siinches long inches diameter` so that the gage dog is raised and let down by the horizontal motion of the lever. Pins are driven in the head block, one near the hand end of t-he lever and one near the other end, on the side next t-he slide and castings, to prevent the lever swinging or mov ing too far, it being necessary when the dog is raised to throw it a little back of a per-` pendicular line so that it will be prevented from falling forward again by its own weight` and when let down toward the rabbet it is sufficient that it be let partly down, say degrees.

The tail block (B, Figs. l` 2, 4) is the same length as the head block and pro-jects over the frame of the carriage on the back side of the carriage, that is, the side from the log way, about 10 inches. The tail block is 18 inches wide, is rabbeted down to receive the end of the log in precisely the same manner as the hea-d block, and the rabbet lined with band iron in the same manner. Plates o-f iron on the top and castings of the same size and pattern forming horizontal grooves for dog-slides, are fasi rabbet.

tened in the same manner and' in the same relative position as on the head block before described. Y Y f Y At the center ofthe block between the slides an iron plate 3 inches widefisscrewed .down to prevent the dogs sliding quite together, andso interfering withthe saw Vwhen 1t runs through the log.

f Slides with dogs attached in the saine way as `described in the head block andof `the same construction move in the horizontalV grooves in the same manner with the exception hereafter particularly described. The dog-slide for the first end of the tail block (p) that is, the end next to the logway instead of the projection downward,

as in the corresponding slide in the head block, is cast with notches or teeth on the under side (N Figs. 5 and 7) extending'the whole length ofthe slide. notches are 2% in. long, that is, extending 2% inches across the bott-om, or under side of the slide. The teeth or notches are perpendicular on the side toward the first end of the head block, and standing the other `way at an angle of 45 degrees. These notches or teeth are designed for a hand O toV work in, which will be described hereafter. A tooth P, Figs. l, 2, is made in the dog leg next the center of the nail block lower down than the p These teeth orV inches deep and #gf in.` apart essarv.

The gage dog (g) for the other end of the tail block is constructed after the same fash ion as the other dogs, except that the tooth next the center of the blockis drawn out, or extended back about 8 inches making a T Fig. 6 with the leg of the dog, and when the dog is turned down on the rabbet, forms with the tooth a perpendicular gage of l19. inches in length. The slide containing the gage dog of the tail block is held by means of a screw Q, and plate u similar to Z and m before described.

A mortise is cut in the tail block, where the saw comes, at the center of the `block (r) 3 inches wide lefinches deep below the hori Zontal part of the rabbet, and into the tail block horizontally 5 inches beyond the This mortise is filled with a block driven Vtightly in, and can be driven out when necessary by a pin from the opposite side or edge of the tail block. The saw'calf is cut into thisblock, and when by the `un even motion of the saw the saw-calf becomes inconveniently large a new block is put in.

A groove R, Fig.. 4, is cut in the tail block, in the; line of the dog-slides from the lend of the tail block opposite the log way, to within ten inches of the other end. This groove passes under the slides, is 213 inches wide and 3,- in. deep, except the 12inches of the groove, toward the endof the tail block lnext the log way, which is mortised outfto izo the depth of 24 inches, and width of 3' cast iron in. thick, is made to occupy that part 0f thel groove mortised out as llast be-V foref described, and movable in it lengthwise the groove. A hand is made of

wrought iron

5,5. in. thick, of length and breadth to move freely up and down in the box. A rivet passes through the box horizontally, near the end of the box, toward the log way, about half way from the top to the 'bottom of the box, and through a hole in the end of the hand. The rivet holds this end of the hand, admitting a play ofthe other end up and down, the hand turning on the rivet as a hinge.

A steel. spring T, Figs. 5, 7, 6 inches long, 1 inch wide, is riveted to the movable end of the hand, on the under side. The other end of therspring rests on the bottom of the box. This spring causes the end of the hand, to which it is attached, to rise unless drawn down in the manner hereafter described. The end of the hand which is movable as before stated is slightly turned up, and pointed with steel, andL works in the teeth or notches before described in the bottom of the slide. The rivet which fastens the spring to the hand as before described, is formed with an eye on the under side of the spring. T0 this a cord U is fastened, which passes down through a hole in the bottom of the box, and through the tail block, by a mortise or hole cut through the block one inch wide by 6 in. long, so that the cord may move with the box. The other end of the cord is attached to a lever V o as hereafter described, Figs l, 2 and 4.

AnV iron bar w, Figs. l, 4, 5 and 7, 14 inches wide, in. thick is riveted to the end of the box next the center of the tail-block, and lies, and is movable in, the groove before described, under the dog-slides, extends. ing to the end of the tail block, opposite the log way, being about 5 feet long. The end of the bar passes into the mouth of a crank, S, Figs. l, 2, 5, and is held by a bolt passing down through the jaws of the crank through a hole in the end of the bar, forming a joint or hinge with the end of the crank. This bar vis covered in the groove in which it works by a plate of sheet iron, to prevent the saw dust getting into the groove l and impeding the freemotion of the bar in the groove. The end or arm of the crank (5) to which the bar is attached in the manner described, is 7 inches long, of Wrought or cast iron 1% inches square, lies horizontally and crosswise of the tail block, resting on it, running back from the before described bar',

toward the end of the carriage. The crank Yforms an elbow or turnat right angles, passfirst described arm and ,14 inches long. v The end of the crank turns down about three inches, isV rounded, and on vit a cast iron roller, called a friction-roller (t) 4 inches in diameter 132 inches thick, turningy horizontally on the end of the crank, and held by a washer riveted on the bottom end of the crank. The motion of the crank is horizontal, and being connected with the end of the bar as vbefore described gives motion to the bar, box, and hand in the groove before described.

An eye X, is formed to the crank, near the end and just above the friction roller,

on the side toward the carriage frame. TheV crank is let into its place in the tail block, by a mortise cut into the end of the tail block, and rests against iron boxes at the top and 'bottom of the tail-block, on the side Of the crank from the end of the tail block. After the crank is let in, it is held to its place by a piece of wood 1% inch thick, 12 inches long, 7 inches wide, fastened by bolts or screws to the end of the tail block, with a projection in the form of a tenant, which fills the mortise by which the crank is let in Land presses against the crank.

A wooden spring (u) of tough elastic timber, 2 inches square, 7 feet long, is fastened at one end on the inside of the carriage frame by a bolt passing through it andy through the carriage frame at such point between the head and tail block, that the other end of the spring shall extend back l2 inches beyond the tail block, passing` under the tail block. The spring is so shaped where it is fastened to the carriage that theother end of the spring stands out about 16v inches from the carriage. This end of the spring is connected by a cord (o2) to the eye. in the end of the crank ,before described. Y Y

A wooden lever (Vo) Figs. lV and 4, 4 feet long is fastened to the tail block on the side or edge next the end of the carriage, by a screw or bolt through the center of the lever into the tail block. This lever is so placed that one end comes out about even with the eye, ln hand Spring, befOI'e d6- vscribed, Vand is Connected to it by'the cord lfastened to theeye in the steel spring as before described. The use of this lever is,

by bearing down the other end, to draw down the hand anddisengage it from ythe teeth or notches in the bottom of the dog izo . slide before described. The lever is kept in this position when desired by a hook fas-` tened to the tail block near the other end of the lever, which catches on to the end of the lever.

The dog-ears are 2113 inches high, inch thick, 8 inches apart on each slide. The feet of the dogs are turned or bent the same way and go into the ears from the side next the center of the head b-lock or tail block as the case may be, and are held in by a washer and pin. The dog teeth at the edge or end which enters the log are made half an inch wider than the upper or back part of the tooth, so that when driven into the end of the log the wood closes around the end of the tooth, and holds it faster to the log, as at Fig. 6.

A plank (C) Fig. 1, l0 feet long, 2 inches thick, 13 inches wide, lying on the'lioor of the mill, on the side of the `carriage oppoi site the log way, 4 inches fromthe carriage frame parallel with it, is held by a pin passing through one end of the plank into the floor of the mill. The pin which holds the plank at this end is about 2 feet from the fender-post toward the tail block. i The plank moves horizontally on' this pin as a pivot or hinge. @n the other end of this plank which extends from the pin last mentioned toward thetail of the mill, `is fastened a piece of plank or timber (fc) 2 inches thick, 13 inches wide in the widest part, 3g feet long onthe longest side or edge, and projecting over the end of the plank on which it is fastened one footj` This upper piece of plank or timber is so placed upon the otherwthat the longest side or edge comes out even with the outer edge of the lower plank, that is, the edge from the car-V riage. The corner of this upper piece of plank toward the fender post, and next the carriage is rounded off from the other corner next the fender post, so as to form partof a circle of 60 inches diameter. The other corner next the carriage is cut olf from about-midway of said piece of plank or tiinber,that is, from the point where the circular part next the carriage terminates and in a line which forms an angle of about 30 degrees with the Vline of the carriage frame. The shape of this piece of plank or timber here described is three sided, the longest side, from the carriage and in a line with the outer edge of the. other plank, the circular,

side toward the fender post and next the carriage. The edge of this upper piece of plank or timber is bound with band iron except the side or edge from the carriage.l

A cord Y Fig. 2, through a `hole about the middle of this upper piece of plank, passes through the floor and over a pulley which is attached to a nog-beam under the floor. The rope is knotted at the end to prevent its drawing through the Plnk, and

a weight D attached tothe lower end-beneath the floor. A pin, No. 1, Fig. 8, in the floor 4 inches from the side of the carriage,

prevents the movable end of the plank from is fastened, and bet-Ween which and the floor a part of the rope passes, can Swing outfrom the carriage and back again without wearing the rope. The pulley is placed under the outer edge or side of the carriage, so that the weight,`by means `of the rope passing over the pulley, draws t-he plank toward the carriage and against the pin in the floor before described.

A plank, No. 11, Figs. 1, 2 and 8, 3 feet long, 16 inches wide, 2 inches thick, extending from the movable end ofthe plank last described toward the tail ofthe mill; space enough being left between itfand the movable end of the other plank C for the latter d to play, and with the Side snug against the outer side of the carriage, is pinned fast to the floor. Twelve inches of the center of this plank is c ut out, crosswise the plank, and on the upper side to the depth of one inch, so as to admit a. slide 12 Figs. 2, 8, one

`foot wide and` one `inch thick. This` slide is movable in horizontal grooves formed by fastening strips or plates of band iron on the top of the `plank and cross wise the plank, projecting win. over each side over the part halved or cut out as before de` scribed. This slide is kept in its place by a pin passing through it and through the plank into the fioor. A triangular block, No. 4, 2 inches thick, 11 inches at the base, and the other twosides forming a right angle-triangle (or, the half of a 11inch square block or plank, cut diagonally,) is pinned fast on this slide last described with the base `or longest side next the carriage frame. The other two sides or edges are bound with band iron are in a line or plane horizontally, with friction roller t, Vand occasion themotionof` the crank bar and hand, in the; manner' and for the purpose hereafter described.

Blocks 13, 14- made in the shapeof a wedge 12 inches thick are fastened on the plank, on each side of the triangular block, with the side end toward the triangular block for Athe purpose of guiding the friction roller and helping it to rise or pass more'easily around the said triangular block. See Fig. 8.

Eight and 1l feet from the fender posttoward the head of the Vmill the postsor ilprights arerset, 3 feet apart, 4: inches square;`

the feet framed into nog-beams, and a piece of timber 4 inches square and 4 feet long 1s framed on the top of the upr1ghts.` The upiodo lio

right is framed into the floor, or into a ngbeam and of the same height as the topV of Y the cross piece.

Y 5tV A wooden lever (y, Figs. l and 2) 3 inches square and 3% feet long passes overthe cross piece or frame last described movab-le horizontally on it, and held at one end on the post back of the frame by a bolt or pin passing down through it and into the post. The lever moves horizontally on this pin or bolt as a fulcrum.

A rope or cord No. 5. through a. hole through the lever where it passes over the cross piece, through the cross piece, and down through the floor to the mill, knotted at the vtop to prevent its drawing through, has a weight No. 6 attached at the lower end.v A pulley is set in the cross piece on each side of the hole through which the rope passes, on one or the other of which pulleys the rope works, as the lever is moved horizontally from the center of the cross piece toward one end or the other of'it. When the force moving the lever is taken off, the weight underneath by means of the rope' and pulley, brings it back to its place. The end of the lever reaches over the end of the headblock about 3 inches, sothat when the saw is running through the log and the carriage moving towardv the head of the mill the hand end of the lever which is fastened to the headblock as before described comes against and in contact with that part of this lever which projects over the head block, the lever on the headblock turns horizontally on its* center pin and the gagey dog connected as before described to this lever is raised up. This lever moves till it comes againstthe pins placed'in the headblock for that purpose as before described. The other lever withY the weight then gives way or moves around till lit passes the lever on the head block, and isV then brought back to its place bythe weight attached to the rope. When the carriage is gigged bac-k the levers work in the same manner, only they come in contact on the other side, and the gage dog is consequently thrown down or forward.

The design and application of the several parte beforedescribed will be further eX- plained by describing' their operation in the process of` sawing. The first thing properly to be done is to set the gage dogs for the purpose of regulating Ythe thicknessfof the stuff to be sawed. This is done by moving the gage dog in the headblock as the case may be, till the gage, that is the leg and'tooth of the gage dog neXt the saw,'stand at a distan ce fromt-he saw equal to the thickness of the stuifto be sawed,that is, l inchl ormore, or

the end ofthe tail block as above stated.

less, as the case maybe. The gage dog in the tail block is set in the same manner. Thelog is then dogged, with the dogs on the log-way side of the carriage (the gage dogs being thrown back) vand the slab taken ofi' from the side of the log neXt the gage dogs. The saw runs quite through the log and the slab falls down on the ratchet. The dog slides are then slipped back toward the end of the head and tail blocks, and the teeth driven into the log near the sidey neXt the log way.

In order to move the slidein the tail block the lever before described at the tail block and connected by a cord to the hand under the slide, is borne down at 'the other end and held by the hook before described,and consequently the hand which works in the teeth on the under side of the slide is held down, so that the slide may be moved back toward The log' Ybeing dogged as last described,

the hook is taken oii1 the end of the lever and Y 1 the hand let up into the notches in the bottom of the slide. The gage dog in the tail 'block' is turned down on the rabbet, the perpendicular gage' before described necessarily standingat a distancefrorn the log where the saw has, run through in taking 'ofi' the slab equal to the thickness of the board next tobe sawed.` i

The endof the crankfon which the friction roller" is, isthen pushed out till it stands 7 or 8 inches from the side of the carriage, straining the spring, which is connected by a cord as before described .to the eye in the end of thel crank,A also moving the boX and hand in the tail block black from the center toward the end-of theA tail block the hand working over the notches or teeth,l as the slide moves. .The wooden spring being strained as before described, exerts aV force or tendency to draw the boX and hand connectedV with theV crank as'before described, toward the. center of the tail block, which is prevented Vby the hand catching in the teeth`on the bottom of the slide-the power of the spring not being great enough to move t-he slide and dog which is fast in the log. The carriage is next gigged back; and gigging back the gage dog in the head block is thrown forward by the action of the lever on the head block and the lever on the frame near it, as before described. The friction roller strikes against the circular edge of the piece of plankfbefore described to which the weight is hung.V The end of the crank on which the Vfriction roller turns is consequently crowded or pressed toward the carriage. They .other end ofthe crank consequently moves in the opposite direction and with it the box, hand, slide,rdog and log, till the log comes in contact with and pressesVV against the perpendicular gage before described, which stopsit and prevents its moving farther. The lplankagainst which the A is gigged back again.

friction roller is bearing then gives way moving on the pin which holds the other end of the plank as before described, and swings back from the carriage till the friction roller passes it, and is then brought to its place again by means of the weight, cord and pulley before described. The friction roller nextI strikes against the side or edge of the triangular block before described which bears the end of the crank from the carriage and consequently moves the box connected with the otherend, and the hand under the slide in the opposite direction, the hand working in the teeth or notches of the slide till the friction roller has passed around or over the said triangular block; by which operation the hand gets a new hold in the teeth of the slide farther back from the center of the tail block, so as to draw the log up to the gage as before, when the carriage The carriage being gigged back, the slide in the head block, and withit that end of t-he log is moved or slid up vtill the log comes in contact with and presses against the gage dog, this done by the sawyerwith a mill bar, using it as a lever in the cogged or notched plate, which is fastened on the slide as before described, and in the manner before described. The gate is then hoisted and the saw runs through the log in the same manner as before leaving no stubshot. The board is raised over the gage dog in the tail block, (the other gage dog being thrown back by the levers as before described) and falls down on the rabbet or is removed. The carriage is gigged back again, all the parts working as before till the log is sawed up.

In sawing thick stu, the triangular block, which is fastened to the slide in the manner before described, is moved and fas tened farther out from the carriage, so as to give the end of the crank a farther motion or sweep, in passing over or around the point of the said triangular block, and consequently to move the hand farther in the teeth or notches of lthe slide, giving it a longer hold, which is necessary, as the log in being set to the perpendicular gage at each time requires to be moved farther to come in contact with it according to the thickness of the board taken out.

When the carriage is moving toward the head of the mill, that is when the saw is running through the log, the friction roller comes in contact with the slant side or edge of the other block or piece of plank through which the rope passes over the pulley as before described, bears it out, the plank turning on the pin in the other end till the roller has passed the block. The weight below by means of the cord and pulley then draws it back to its place parallel with the carriage.

In the foregoing description the carriage at the end of the log on the tail block.k It

consists of a horizontal plate' 7, Fig. 13, shaped so as to fit the sides of the ears of the tail blockslide, with a right-angled piece taken out of one corner so as to leave a space 8 to admit the end ofthe log therein; from which plate rises a perpendicular standard 9 perforated with apertures toadmit a horizontal dog 10 driven into the side of the log toward the log way. This standard is placed directly over the rabbet in the tail block.

VThe gage dog g of the tail block is also` thrown back out ofthe way when a cut has been made in order to remove the board and` is brought down into its place again when. i

the log is to be pushed up against it in the following manner: A vibrating lever, 15

Fig. 1, similar to lever O of the head block is attached to the gage dog by a link also in a similar manner. To the end of the lever is attached a strap 16 which is passed over a pulley 17 and under the rail block and fastened to a Slide 18. From the same end of the lever there extends another strap 19 down through an opening in the tail block onward horizontally to a pulley 2O at the side of the carriage over which it extends to the before mentioned slide where it is made fast.

The slide 18 for moving the lever 1 and gage dog (g) is moved by coming in contact with a spring or weighted stop 21 and by means of a lever 22. The spring or weighted stop passes vertically through the floor of the mill and turns on a pin passing through ears erected thereon. The lever vibrates horizontally on a pin inserted into V a block raised upon the floor.

Vhen the carriage has advanced as far as it is intended to go the mill gate is closed in the usual manner. In letting down the gateA a wedge fastened on the side of the gate staff comes in contact with the lever 22, presses one end back while the other end carries back the slide which draws the strap 19 and this vibrates the lever 15 which throws back the gage dog g.

In gigging back the carriage the slide comes in contact with the weighted or spring stop 21 and meeting with a resistance thereby causes the slide to be moved back again, thus vibrating the lever in the opposite direction and returning the gage dog to its former position. y

The invention claimed and desired to be secured by Letters Patent, consists inl. The method of fastening'the slides of the dogs and gage dogs as before described.

2. The combination and arrangement .of the crank, the bar attached to it, boX, hand and spring, teeth in the bottom of the slide, lever on the back of the tail block to hold the hand down, the Wooden spring fastened to the carriage andattached by the cord to the end of the crank, the blocks against which the friction roller Works and the parts to which they are attached fastened to the floor and the Weight 'as before described.

3. The use of two, or double slides in each block, that is, die' head block and adi block,

instead of one, or a single slide; and the 5. The additional pida, sndnddfddnd dogV for supporting Vlarger logs as before described. v

6. The combination vof the parts of the apparatus for moving the gage dog of the Ytail block asbefore described.

HEZEKIAH T'HRBER.

Witnesses: WM. P. ELLIOT, WM. BISHOP.