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GIFT OF 
 
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 LIBRARY 
 
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GEOMETRICAL 
 
 STAIR BUILDER, 
 
 SIMPLIFIED. 
 
 By JOHN" THOMAS. 
 
Entered according to Act of Congress, A. D. 18B3, 
 
 BY JOHN THOMAS, 
 In the Clerk's Office of the District Court of the United States for the Northern District of California. 
 
 Any infringement on the copyright of this book will be prosecuted to the utmost extent of the law. 
 
 GIFT OF 
 
 Bancroft 
 LIBRARY 
 
 TOWNE & BACON, BOOK AND JOB PRINTKBS, 536 CLAY STREET, SAN FKANCISCO. 
 
INTRODUCTION. 
 
 THERE has been so much said and written on the art of Stair Building for the last few 
 years, that it has been considered as bad as heresy to pretend that a hand rail could be 
 got up without the use of prisms, parallelograms, ordinate lines and tangent boxes, and 
 a host of lines and terms accompanying them ; although nine-tenths of the mechanics at 
 the sight of such geometrical problems turned from them in disgust, and could only 
 know what they heard related of them. Even the practical Stair Builder had to bring 
 his book along with him to his shop, like a school boy, for fear he might forget one of 
 the many lines given therein and in several cases they are entirely wrong and then 
 spend half a day at what this work teaches to do in ten minutes or less. Is there a man 
 that will go to the trouble to set out and make two moulds, one to cut his stuff by and 
 the other to slide, which is termed a slide mould, whilst he can make one do ; or crack 
 his brain studying for hours over any of the preceding works on Stair Building, whilst 
 he has only to look at the " Geometrical Stair Builder Simplified," which teaches him to 
 set out a wreath for any stairs with eight or ten lines, and in as many minutes. 
 
 In presenting this work to the mechanic, all technicalities and high sounding phrases 
 are carefully avoided, so that any man can understand it. For simplicity and correct- 
 ness it cannot be equaled ; for quickness, I defy the world to beat it, unless a rail can be 
 set out without a line, or done by magic. 
 
 JOHN THOMAS,, 
 
 STAIR BtriLDER'v ' r-; i V 
 
 SAN FRANCISCO, JANUARY, 1863. 
 
 t 
 ' , 
 
Tlate I. 
 
 Fig. 1 is a quadrant ; to find the stretch out B C the quadrant, F C the diameter, 
 with the distance F C in the compass, describe two arcs, cutting each other at 
 G, and draw the tangent B E parallel to F C, cutting the quadrant at B ; from the 
 point G draw a line through C, cutting the tangent at D, then B E is the required 
 length. 
 
 Fig. 2, another method. A B C is a semicircle ; A C the diameter, with the distance 
 A C as a radius ; describe two arcs, cutting each other at G, draw the tangent D E 
 through B, extended parallel to A C, the diameter ; draw the lines G D and G E 
 through the points A and C, and from the equilateral triangle D E G, any side of which 
 is equal to the semicircle ABC. 
 
 Fig. 3 shows the method of setting a gauge for an octagon without drawing the figure, 
 the square being given from P, open the compass to O the center, and draw the arcs 
 O C, then C is the point to set the gauge. 
 
 The attention of the workman is called to Plate II, Fig. A and Fig. B A. The 
 lengths of the tangents are found at Fig. B. A. From the base line 1 8 the perpendic- 
 ular is drawn and united by the hypotenuse, and from the relative positions of the tan- 
 gents to the perpendicular and hypotenuse lines the spring bevels are found. To apply 
 .them s^/J*late III. 
 .. ,'JWhen th'fe, taaigents are of equal length, one bevel squares both ends. 
 
 In no case does it require thicker stuff than the width of the rail to get out a wreath 
 for any stairs. 
 
PL ATP, I. 
 
 Fig. 3. 
 
 (o 
 
PLAT I; L'. 
 
 3 
 
OPlate II. 
 
 Fig. A, the tangents, is at obtuse angles ; 1 2 8, the tangent enclosing the center line 
 of the rail ; 1 8, the base line ; 8 3, the perpendicular. Fig. B A is a board with two 
 gauge lines drawn on it equal in width to one of the tangents at 1, draw a line at right 
 angles to 1 3, and on it place the pitch board, the point resting at 1, and where the 
 pitch line cuts the gauge line at 2, then 2 1 is the length of the bottom tangent ; from 
 
 1 raise up to 3, the heighth you want to overcome, and draw the line 3 2, which is the 
 length of the upper tangent, make 8 3, Fig. A, equal to 1 3 on the board, and draw the 
 hypotenuse 1 3, then make 1 2, Fig. A, equal to 1 2 on the board, and 2 3, Fig. A, equal 
 to 2 3 on the board, and you have the required tangents, and when placed in position 
 with two pitches, will cover exactly the tangents 1 2 8, on the ground plan, to find the 
 bevel for the joint joint at 3 set one leg of the compass in 3 and open it to 2, revolve 
 
 2 round to 7, then take the distance 1 2, and put one leg in 8 and cut the arcs at 7 ; 
 then draw the line 7 3, then take equal distances on these two tangents 3 7, 3 2, at T T ; 
 then square down to J J, and from J J describe two arcs cutting each other at M, and 
 draw two lines from this point to J J, and the angle formed is the required bevel for 
 the joint at 3. To find the bottom bevel for the joint at 1, reverse the bottom tangents 
 on the perpendicular and hypotenuse lines, as shown at Fig. B, and you find the bevel 
 in the same manner as you found the middle bevel. 
 
 Fig. C and Fig. D, the tangents are at right and acute angles. Fig. B C is the board 
 for Fig. C, Fig. B D the board for Fig. D, the tangents for both of these figures are 
 found in the same manner as for Fig. A. The dotted lines show the tangents reversed, 
 for to get the bottom bevel, the tangents and bevels for all rails are found in the same 
 manner as Figures A and B. 
 
III. 
 
 Fig. A shows the ground plan of a platform stairs with the risers in the cylinder. To 
 draw the face mould ; 128,. the tangents, enclosing the center line of the rail, 1 8 the 
 hase line, 8 3 the perpendicular. Fig. B is a board with two gauge lines equal in width 
 to one of the tangents ; at 4 draw a line at right angles to 4 3, extended hoth ways on 
 this line place the pitch board, letting the point 5 project beyond the line 4 3 the same 
 distance as from 1 to 5 Fig. A ; from 4 to 3 raise up the height of one riser and a half, 
 which is the required height, then draw the pitch line cutting the gauge line at 2, and 
 1 2 is the length of the bottom tangent ; draw the line from 3 to 2, which is the length 
 of the top tangent, make 8 3 Fig. A equal to 1 3. Fig. B, and draw the hypotenuse 3 1, 
 then make 1 2 Fig. A equal to 1 2 Fig. B, and 2 3 Fig. A equal to 2 3 Fig. B, and you 
 have the required tangents. 123, when placed in position with 1 resting in 1 on the 
 ground plan, 2 3 will exactly cover 2 8 on the ground plan. The bevel for the joint 3 
 is shown at M, and the bottom bevel is found by reversing the tangents on the perpen- 
 dicular and hypotenuse lines ; with a bevel transfer the tangents 123 Fig. A to Fig. P, 
 the board you cut the pattern from, intersect the tangents by dividing each into eight 
 equal parts, and the intersected line is the center line of the rail ; with half the width 
 of the rail in the compass, put one leg in the center line and describe arcs on each side 
 of it, which gives you the pattern an equal width. The one pattern answers for the 
 top and bottom wreaths ; the joints are cut at right angles to the tangents, and square 
 from the face of the plank ; the bottom bevel is applied by putting the stock on the 
 face of the wreath at 1, the blade passing down through the center with the end of the 
 stock pointing in to the stairs ; the top bevel is applied reversed, with the end of the 
 stock pointing out and the blade passing down the center ; from these lines square the 
 rail. 
 
PLATE ,'i. 
 
 Fig. P. 
 
 Fig.B 
 
 
1 K 
 
relate IV. 
 
 Fig. A is the ground plan of a platform stairs with the risers at the springing of the 
 cylinder. To draw a face mould : 1 2 8 the tangents enclosing the center line of the 
 rail, 1 8 the base line, 8 3 the perpendicular, Fig. B the board with the two gauge lines 
 equal in width to one of the tangents ; from 1 draw a line at right angles to 1 3, and 
 on this line place the pitch board, the point resting in 1 , as you require to raise but one 
 riser from R to S ; then divide the heighth of the riser on the pitch board and square 
 over to 3, and draw the lines 123, which is the required length of the tangents ; make 
 8 3 Fig. 1 equal to 1 3 Fig. B, and draw the hypotenuse 1 3, then make 1 2 equal to 1 
 2 Fig. B, and 3 2 equal to 3 2 Fig. B, 1 2 3 are the tangents. The middle bevel is 
 found as usual at M, and the bottom bevel is shown at Fig. A B with the tangents 
 reversed on the perpendicular and hypotenuse lines with the bevel ; transfer the tan- 
 gents to the board you cut your pattern from, and intersect the tangents and make the 
 pattern as usual, leaving some stairwood at 1 to connect with the straight rail. 
 
 Fig. R shows the second flight starting from a level landing or floor round a cylinder 
 to flyers. 12845 the tangents enclosing the center line of the rail, 1 8 the base line, 
 8 3 the perpendicular, Fig. B C the board with the two gauge lines from 1 to 5, is the 
 required heighth ; 1 2 the pitch line, from 2 to 4 divide into two equal parts and square 
 over to 3 and draw the lines 12345, which is the length of the tangents for the 
 upper and lower wreaths ; make 8 3 Fig. C equal to 1 3 Fig. B C, and draw the hypot- 
 enuse 1 3 ; make 1 2 equal to 1 2 Fig. B C, and 2 3 equal to 2 3 Fig. B C, 1 2 3 are 
 the required tangents for the upper wreath ; extend the tangent 2 3 to 4, and make 4 3 
 equal to 3 2 ; from 4 square down to 5, and make 5 4 equal to 5 4 Fig. B C ; transfer 
 the tangent to the board you cut the pattern from, as at Plate 3, Fig. P. The bevels 
 for the upper wreath are found as usual ; the bevel for the lower wreath at the joint 5, 
 is shown at 3 Fig. B C. The lower wreath can be set out by the compass, as the tan- 
 gents are nearly equal in length. 
 
I^late 
 
 A shows the ground plan of a geometrical 'staircase with winders round the semicircle. 
 Fig. B shows the manner of setting out the face string before it is bent round the drum. 
 It is generally one and a half inches thick, cut out in the center as shown at V Y. The 
 yeneer, which is equal to the stretch out of the semicircle ABC, W W the winders, 
 G G the graduating steps, F F the flyers, P P the splices. If you want to raise the 
 rail so that the long bannister goes over the cylinder, you must not have a graduating 
 step on the lower part of the cylinder, but put a winder in the place of a graduating 
 step between the springing and the flyers ; on the upper portion of the cylinder put a 
 winder in place of the graduating step, and one graduating step between it and the 
 flyers, in order to give room to form an easing between the upper wreath and the 
 straight rail. To form the upper and lower easing you set out an elevation of the flyers 
 and winders, and the angle formed between is the place to make the casings, as shown 
 at Plate 9. If the face string is to be moulded, gauge the width of the opening on the 
 string before bending it ; and when bent, cut it off and set it back the required depth 
 for the moulding, and then plant in the moulding, which will hide the saw kerf. 
 
PLAT I: 
 
 Fiq A 
 

Fiy.B 
 
 Fig. P. 
 
Ilate 
 
 Shows the method of drawing the face mould for the geometrical staircase shown at 
 Plate 5. With the short bannisters over the winders, enclose the center line of the rail, 
 as usual, with the tangents I 2 8 on the ground plan ; Fig. A, 8 1 the base line, 8 3 the 
 perpendicular ; Fig. B the board with the two gauge lines equal in width to one of the 
 tangents on the line 1 4 ; place the pitch board and draw the pitch line 1 2, and from 
 4 raise up to L, the number of risers in the cylinder ; divide it in two equal parts, 
 squaring over to 3, and draw the line 3 2 ; make 8 3 Fig. A equal to 1 3 Fig. B, and 
 draw the hypotenuse 1 3 ; make 1 2 equal to 1 2 Fig. B, and 2 3 equal to 2 3 Fig. B, 
 and 123 are the required tangents. Transfer them to Fig. P, the board you cut the 
 pattern from, and proceed as usual with the formation of the mould. The one pattern 
 answers for the upper and lower wreaths. The bevels for both ends are found as usual 
 in all cases. 
 
Fig. A is the ground plan of a staircase, the lower part constructed of flyers, with 
 winders round the semicircle to land on a level floor. Fig. B the face string without a 
 graduating step. Fig. C the rail, the lower wreath forming a perfect easing over the 
 flyers, L the landing, with the rail raised four inches over it, so that the long bannisters 
 can go on the landing. E E Fig. B, the easings of the cylinder ; P the splice to con- 
 nect with the face string. 
 
PLATE 7. 
 
. 
 
W<ATT: a. 
 
HPlate 
 
 Shows the manner of getting the face mould for the stairs Plate 7. 12845 Fig. A, 
 the tangents enclosing the center line of the rail ; 1 8 the hase line ; 8 3 the perpendic- 
 ular. Fig. B a hoard with two gauge lines equal in width to one of the tangents ; from 
 the line 1 3 square over to 4, and on it place the pitch hoard from 4 to L, the heighth 
 of four risers, and four inches from where the pitch line cuts the gauge line at 2, divide 
 from 2 to L in two equal parts and square over to 3, then draw the line 2 3, and make 
 8 3 Fig. A equal to 1 3 Fig. B, and draw the hypotenuse 1 3 ; make 1 2 Fig. A equal 
 to 1 2 Fig. B, and 2 3 equal to 2 3 Fig. B, and draw the tangents 1 2 3 to form the 
 upper wreath ; extend the tangent 2 3 to 4, and make 3 4 equal to 3 2 ; from 4 square 
 down to 5, and make 4 5 equal to 4 5 on the ground plan. Transfer the tangents as 
 usual, and form the pattern, leaving ahout three inches of straight wood on the upper 
 wreath at 5. The bevels for the lower wreath are found as usual ; the bevel for the top 
 wreath is shown at T Fig. B. 
 
JPlate IX. 
 
 Fig. A shows the ground plan of a staircase, the lower part of which is constructed 
 of flyers with winders round the semicircle to land on a level floor. 
 
 Fig. B the face string ; W the winders, with one winder in the place of a graduating 
 step, in order to raise the rail so that the long bannisters can go round the cylinder. 
 
 Fig C the rail, with the center line raised up four inches from the corner of the step 
 and riser, which gives a most graceful easing at E ; if there was a graduating with the 
 winder, it would make the easing too long and too far from the curve of the rail as it 
 passes round the cylinder. If you want to put the short bannisters over the winders, 
 you can do it on this plan ; but it would be better to put in two graduating steps, and 
 by so doing you produce the same easing as shown at E. 
 
PLATE !). 
 
PLATE If i. 
 
 fig. P 
 
To draw the face mould of the hand-rail of the stairs, as shown at Plate IX. 128 
 4 5 Fig. A, the tangents enclosing the center line of the rail ; 1 8 the base line ; 8 3 the 
 perpendicular. Fig. B the board, 1 4 the gauge lines, 4 L the heighth of four risers, 
 123 the length of the tangents ; transfer those tangents to Fig. A as usual, 12345 
 Fig. A are the tangents. 
 
 The middle bevel for the joint at 3 is shown at M ; the bottom bevel for the joint at 
 1 is found as usual by reversing the tangents. The bevel for the upper wreath is shown 
 at the angle T Fig. B. 
 
relate XI. 
 
 To draw the face mould for a staircase with winders, landing the well hole, formed by 
 two quadrants of unequal radii. 12845 Fig. A, the tangents enclosing the center line of 
 
 
 
 the radii ; 1 8 the base line ; 8 3 the perpendicular ; Fig. B tlio board with three gauge lines 
 equal in width to 4 8 8 2 Fig. A. From L square over to D, and on this line place the 
 graduating step with the point resting at 1 ; then draw the pitch line to 2, which is from 
 1 to 2, the length of the bottom tangent for the lower wreath ; from L raise up the 
 heighth of four risers and four inches, then draw the line 4 2 through. 3, and 3 2 is the 
 length of the top tangent of the lower wreath, and 3 4 the length of the bottom tan- 
 gent of the upper wreath ; make 8 3 Fig. A equal to 1 3 Fig. B, and draw the hypote- 
 nuse ; make 1 2 equal to 1 2 Fig. B, and 2 3 equal to 2 3 Fig. B. To form the upper 
 wreath, extend the tangent 3 2 to 4, and make 4 3 equal to 4 3 Fig, B ; from 4 square 
 over to 5, and make 4 5 equal to 4 5 on the ground plan Fig. A. The bevel for the 
 joint 3 is shown at M ; the bottom bevel is found as usual. The bevel for the upper 
 wreath is shown at T Fig. B. 
 
PLATE It. 
 
XII. 
 
 
 
 To draw the face mould for a quarter circle rectangular stairs. 128 Fig. A, the tan- 
 gents enclosing the center line of the rail ; 1 8 the base line ; 8 3 the perpendicular, 
 which is' equal in heighth to four risers ; 1 3 the hypotenuse ; Fig. B the board with the 
 two gauge lines equal in width to one of the tangents. From 4 to L, the heighth of four 
 risers, divide that line into two equal parts at 2, and draw the lines 1 2 and 2 3, which 
 is an equal length with the distance 1 2 Fig. B in the compass ; put one leg in 1 Fig. A, 
 and describe the arcs at 2, then change the compass from 1 to 3 and cut the arcs at 2, 
 and draw the tangents 1 2 2 3, as they are an equal length, the bevel B will square both 
 ends. 
 
 REMARK. At the time of building the stairs, set out the tangents on the board Fig. 
 B, in order to have the tangents an equal length, and for them to come parallel to the 
 pitch line of the graduating step. From 4 to R, the heighth of one riser, square over 
 to O, then draw O W parallel to R 4, and from 1 to "W is the width of the graduating 
 step. If the stairs should be built, extend the tangent 2 1 down until it cuts the pitch 
 line of the flyers; the same with the tangent 2 3, and the angles formed will be the 
 casings. 
 
XXIX. 
 
 
 
 The ground plan of a staircase with winders round the quarter circle, starting from a 
 newel and miter cap to draw the face mould in one piece with a perfect easing at the 
 newel cap. 12834 the tangents enclosing the center line of the rail ; 4 8 the base 
 line of Fig. B ; 8 3 the perpendicular ; Fig. B A the board with the two gauge lines ; 
 G the graduating step, with the point resting at 4. From 4 to L raise up the heighth 
 of three risers and two inches, which is the required heighth from the bottom of the 
 newel cap to the center of the rail at 4 Fig. B, where the pitch line cuts the gauge line 
 at 5. From 5 to L divide in two equal parts at O, square over to 3 and draw the line 
 354, w r hich is the length of the tangents for Fig. B ; make the perpendicular 8 3 Fig. 
 B equal to 4 3 Fig. B A, and draw the hypotenuse 3 4 ; transfer the tangents as usual, 
 453 Fig. B A to 4 5 3 Fig. B ; 1 8 the base line for Fig. A ; 8 3 the perpendicular, 
 equal in heighth to O L Fig. B A ; make 3 2 equal to 3 5 Fig. B, and 1 2 equal to 1 2 
 on the ground plan. With the bevel transfer the tangents of the upper half of the 
 wreath to the board you cut the pattern from, as shown at Fig. P ; then transfer the 
 tangents of Fig. A to the same board and unite the two 3 3, keeping the lines 3 5 and 
 3 2 on a straight line ; intersect them as shown, and when in position with 1 2, covering 
 1 2 on the ground plan, 2335 will exactly cover 2 8 3 on the ground plan, and 5 4 
 will exactly cover 3 4. Also having the pitch of the graduating step G, always leave a 
 few inches of straight wood at 4 and at 1, for the purpose of squaring up from the bot- 
 tom to make the miter for the newel cap. The bevel for the joint at the newel cap is 
 shown at B Fig. B A. The bevel for the center of the wreath 3 3 is shown at M ; and 
 to find the bevel for the joint at 4, you reverse, as usual, the tangents of Fig. B, then 
 you have three points to square the a il from. 
 
PLAT.K 73. 
 
PLATE Ik. 
 
 A G \ 
 
Flate 
 
 To draw the face mould for a hand rail over winders. The ground plan is formed by 
 the quadrant of a given radius, with the arcs of a circle added by a smaller radius, start- 
 ing from a newel and miter cap. 
 
 It is useless to describe this drawing, for it would be only a repetition of Plate XIII, 
 and all former plates. You see that the principle is the same, and that they are num- 
 bered alike ; the only difference is the arcs of a circle added. Bear in mind that the 
 wreath, starting from the newel cap at Plates XIX and XXI, is just the same as this, 
 and the wreaths landing are the same as in Plate XV. 
 
Tlate 
 
 Shows the ground plan of a staircase with winders round the quarter circle, landing 
 on a level floor. To draw the face mould for the wreath over the winders and the eas- 
 ing over the landing at L in one piece, with the long bannisters over the winders : 1 2 8 
 
 3 4 the tangents enclosing the center line of the rail ; 1 8 the base line for Fig. A ; 8 3 
 the perpendicular ; Fig. B A the board with the two gauge lines, equal in width to one 
 of the tangents. From 1 to 4 square over, and on this line place the pitch board of the 
 winders G, the point resting in 1, and draw the pitch line, cutting the gauge line at 2. 
 
 
 
 From 4 raise up to L the heighth of four risers ; from 2 to L divide in two equal parts, 
 square over to 3, then draw the line 3 2, and you have the tangents for the lower wreath. 
 
 4 3 the base line of Fig. B, 4 5 the perpendicular ; then make 3 4 equal to 2 3 Fig. 
 B A, and make 4 5 equal to 3 4 on the ground plan ; unite the tangents as at Plate 
 XIII to cut your pattern. The tangent 1 2 Fig. P, when placed in position, will exactly 
 cover 1 2 on the ground plan, and 2 4 will cover 2 3 ; and 4 8 will be perfectly level, 
 covering 3 4 on the ground plan. The bevel for the joint at 5 is shown as usual at T 
 Fig. B A. The bevel for the center at 3 3, is shown as usual at M. The bottom bevel 
 is found by reversing the tangents of Fig. A. 
 
PLATE 15. 
 
PLATE 16 
 
 . H. 
 
To construct the face mould for a hand rail, starting from a newel with a miter cap, 
 the ground plan being either an elliptic curve or the arc of a circle. To find the position 
 of the tangents on the ground plan : Fig. C the pitch board from 1 to 5 is six inches, the 
 heighth of the center of the newel cap from the first step ; from 5 square over to 3, then 
 draw the tangent 8 2 Fig. A, extended ; at 8 place the point of the pitch board ; from 
 the pitch board at 6 to 2, make it equal to 5 3 Fig. C, and from the miter cap draw 
 the tangent 1 2 ; from 2 square up to 7, and where the pitch line cuts at 7, from 7 to 
 8 is the length of the tangent. On the base line 1 8 erect the perpendicular 8 3, and 
 make it equal to 7 2 ; then make 3 2 equal to 7 8, and 1 2 equal to 1 2 on the ground 
 plan, and you have the required tangents ; and when placed in position, with 1 2 rest- 
 ing on 1 2 on the ground plan, 3 will exactly cover 8, and the tangent 2 3 will have the 
 pitch of the flyers. The bevel for the bottom is shown at B ; the bevel for the top is 
 shown at S. 
 
 Always leave a few inches of straight wood at joint 1 to square up to form. 'the miter 
 for the cap. 
 
Shows the face string with the easing E, the pannel P, and also the best manner of 
 putting the step and risers together, B B. The blocking and the risers should be 
 screwed from the back to the step, and the blocking glued and nailed. Fig. A shows 
 the manner of setting out the length of the rail at the newel cap ; and to find the miter 
 of the rail for the cap, from the top of the step to the center of the rail should be six 
 inches, and the center of the straight rail cutting through the corner of the steps and 
 risers at C ; the center of the newel projecting three -fourths of an inch outside the face 
 of the first riser, so that you may have a longer easing at D. Fig. B shows the board 
 you cut the miter of the newel cap in ; T T are two cuts in the board equal to the 
 width of the rail, with a screw in the center to fasten the cap to it. Mark the width 
 of the rail on the cap, and bring one of these marks opposite the cut T ; cut the miter 
 half way and turn the cap round until the other mark is opposite the other cut T, thei 
 
 
 
 cut the miter through and you have it correct from the saw. 
 
PL ATM 77. 
 
AV. 
 
 Ftq.B 
 
 w 
 
Tlate 
 
 Fig. A is the plan of a staircase with the tangents on the ground plan at acute angles. 
 It also shows that no matter in what position the tangents on the ground plan are placed, 
 iccording to this system, the difficulties in stair railing can be overcome by the few sim- 
 ple lines laid down in this work. It is useless to describe this Plate, as it would only 
 3nter into a repetition of Plate XII. 
 
JPlate XIX. 
 
 Exhibits the ground plan of an elliptical staircase. To find the face mould : 1 2 3 
 
 the tangents enclosing Fig. A ; 3 4 5 the tangents enclosing the center line of the rail 
 
 Fig. B ; 5 6 7 enclosing the center line at Fig. C ; 7 8 9 at Fig. E, and 9 10 11 Fig. F; 
 
 5 7 the base line of Fig. C ; 7 7 the perpendicular ; Fig. C C the board with the twri 
 
 gauge lines ; 7 6 and 11 12 equal in width to one of the tangents. On line 7 6 raise up 
 
 the heighth of the number of risers that the base line 5 7 covers ; divide it in two 
 
 equal parts and square over to 5, and draw the lines 7556, which is the length of the 
 
 tangents for Fig. C ; make the perpendicular 7 7 Fig. C equal to 7 6 Fig. C C, and draw 
 
 the hypotenuse 7 5 ; make 5 6 Fig. C equal to 7 5 Fig. C C, and 6 7 equal to 5 6, th< 
 
 tangents 567 will cover the corresponding figures on the ground plan. From the tan 
 
 gents Fig. C C you find the pitch for the lower wreath Fig. B and Fig. A, and also for 
 
 the wreath Figs. E and F ; from the gauge line 11 12 Fig. C C, draw the line 8 9 equal 
 
 in width to the tangent 5 4 Fig. B, then continue the tangent 6 5 to cut the line 8 9 at 
 
 4 Fig. A B. From 5 set down the heighth from the newel cap to the tangent 5 Fig. B, 
 
 then square over to 8 and divide the line 8 4 in two equal parts, and square over to 2J 
 
 and draw the lines 8 2 and 2 4 and 4 5, which is the length of the tangents for t 1 
 
 lower wreath ; 5 3 the base line Fig. B ; 3 8 the perpendicular, equal to 2 5 Fig. A B 
 
 and make 5 4 equal to 5 4 Fig. A B, and 4 8 equal to 4 2, then 5 4 8 is the tangent fo: 
 
 the wreath Fig. B ; 1 3 the base line Fig. A ; 3 8 the perpendicular, epual to 1 2 Fig 
 
 A B, and 2 8 equal to 2 8 Fig. A B, and 1 2 equal to 1 2 on the ground plan. On tb 
 
 board you cut the pattern from, unite the tangents as usual, as shown at Fig. A B, Pla 
 
 XX, which is the wreath to cover from the newel cap to the tangent 5 Fig. B. Th 
 
 length of the tangents for the upper wreath are found on the board Fig. E F ; 7 A 
 
 is equal to the pitch of the tangent 5 7 Fig. C C. From 7 to C is five risers and four 
 
 inches. To raise the rail on the landing, from A to C divide in two equal parts and 
 
 square over to B, and draw the line C B B A, and you have the required length of the 
 
 tangents for the wreaths Figs. E and F, which are numbered 7 A B and BCD. Th 
 
 bevel for the joint D is shown at T Fig. E F ; and the bevel for joint 1 at the newel cap 
 
 is shown at A Fig. A B. The other bevels are found as usual. Plate XX shows the 
 
 patterns. 
 
PLATE -fd 
 

PLATE > 
 
 Fig. C. 
 
 D 
 
 Fig. 
 
 E.F. 
 

PLATE 2 
 
XX. 
 
 The ground plan of a circular staircase. Enclose the center line of the rail with the 
 
 tangents 123,345,667,789.91011. It is useless to describe this rail, as it would 
 
 
 be only a repetition of Plate XIX. Although Plate XIX is elliptical and this circular, 
 
 still the principle is the same ; and as this Plate and Plate XIX are numbered alike, you 
 can read the instruction for Plate XIX, and you will find the wreaths. Figures A B, C C 
 and E F are the boards, to find the lengths of the tangents. 
 

UNIVERSITY OF CALIFORNIA LIBRARY 
 BERKELEY 
 
 Return to desk from which borrowed. 
 This book is DUE on the last date stamped below. 
 
 UBRARY USB 
 
 KDTJ 
 
 21 (j 
 
 J'JNS 1963 
 
 19730 
 
 LD 21-100m-ll,'49(B7146sl6)476 
 
 
YE 01238 
 
 861331 
 
 THE UNIVERSITY OF CALIFORNIA LIBRARY