in Circular ArchiteBure. 145 



pels, fteeples, columns to fupport ponderous roofs, the hol- 

 low ones with ftair-cafes when wanted, niches, cells, cloif- 

 ters, vaults, &c. 



Explanation. 



Fig. I. G is a fingle clump, having its male point inwards 

 on the fide in view ; b is one with the female point inwards 

 on the reverfe of the fame clump. 



Fig. a. a, one with the male point outwards ; b, one with the 

 female point outwards. Each of thefe figures, i and 2, re- 

 prefent different kinds of clumps, which bein^ laid, one kind 

 at a time, in a circular form, with the fame fides uppermoft, 

 will make one courfe : fee fig. 5. for an example of one courfe 

 of clumps, fig. T, a. Then add one courfe of fig. 2, fitted in 

 male and female (or joggled) ; and fo on alternate circles, 

 fig. I and fig. 2, to the end of the length defigned, termi- 

 nating the fame with a caft iron plate. Haunch piece, or key 

 clump, with two male fides fo as to admit of taking down 

 for repairs, &c. This method will form a broken joint, fuch 

 as the one exhibited in perfpeAive view fig. 9. 



Fig. 3. is an elongated clump for forming folid columns, 

 colonnades, &c.; a having its male point invv'ards, and b hav- 

 ing its female point inwards. 



Fig. 4. a clump elongated as in fig. 3- a (hows the view 

 with the male point outwards: b the reverfe of the fame 

 clump, with the female point outwards. Thefe clumps are 

 to be laid into each other in the fame manner as rig. i and 2, 

 to form a column of folid work, of which a fe(£lion is repre- 

 fented in fig. 8. If it is intended to confi;ru6l a circular ftair- 

 cafe with dome-light, &c. on this principle, one or more 

 clumps in each courfe of work (be the fame of brick, earth, 

 {lone, or other material, according to the defign and extent,) 

 muft be of the long kind, to form tha Jlep of the flairs; all 

 the reft of fliort clumps, fig. i and 2, to admit light and ac- 

 cefs through the aperture of afpiral afcent. 



Fig. 5. a, a, a, Uiows the pofition of clumps a, fig. i, ac- 

 cording to the mode of laying ihem, with the male point in- 

 wards : b, b, b, fhows the reverfe of the fame clump with the 

 female- point inward. I'he bottom circle in this and the next 

 figure fiiows merely the pofitlgn which a continuation of the 

 clumps would take. 



Fig. 6. clumps with blank fide? uppcrmofl : thefe are 

 merely for laving the firft courfe on the ground, or, in fome 

 inftances, for faving the expcnfe of a caft iron rim next the 

 flaunch of a branch piece. Their reverfe muft be always in- 

 dented, or joggled, to fit the next courfe of clumps. If it is 



Vol. XV. Xvio. 3a. L rec^uircd 



