EDD

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Cou r er b y cramps, has already been described ; but thoseto ,] e > u pon which the floors rested and depended, seemedSet\ et . rr j an ^ every possible security. It will be seen, in theUp 0tl a section, Plate II. that each floor designedly rested° courses : it will also appear, by inspection, that thesl°pi n J erenc e of the floors was not made to rest upon thee«ntr e Q abutrae nts of an arch, in lines tending toward the^a s a the sphere, of which the under side of the floorW]y portion, but it rested upon a triple ledge going circu-l hi 8 , Un d the two supporting courses. In consequence offyin’u aa ea ch floor been composed of a single stone, thisty'tfld P° n tlie horizontal bearings furnished by these ledges,' V ^ e *t remained entire, have no lateral pressure ort j y. to thrust out the sides of the encompassing walls :r «ally ln effect, the several pieces, of which the floors were8 to nes c ^ rn posed, might have the same property as wholeopg .' e cen tre-stone was made large enough to admit of', n o> from floor to floor, or man-hole, to be mades, de 8 "i.-tt > and being furnished with dovetails on its fourHigjj . e those of the entire solid, it became the means byCo * the stones in each floor were connected together ;Sg] e ^quently, the whole would lie upon the ledges like a'*> by without any tendency to spread the walls. But? tho ae e acc ’dent of a heavy body falling, or otherwise, anyS r .stones should be broken, though this might notp ar) . s Us e as a floor, or its properties as an arch ; yet^Is. 8 Wou ld then exert their lateral pressure against thet^ssar* 11 ^ therefore, as a security against this, it became“° a n<} ^ that the circle of the enclosing walls should bec ' ’I.'hig’ 6 ^ 161 '’ an, d the building, as it were, hooped.

t ' Vou ^ he in a great measure brought about by the^ s crik ec j n .p tbe neighbouring stones together, as alreadyJ’ s °late ’ or . ordinary courses ; but yet this was nof ^fat e S 5 Curit y, because the outside stones might break and0t ’ et ween cramp and cramp : and I suppose, it wasd W 8 °f this kind, that Sir Christopher Wren , in the3ericl u° n th e cupola of St. Paul’s, did not choose to' S(>f V . ? n cramping the stones together, of the coursetor ^ as a common base to the inside dome, and thea °le wit^Pcrting the lantern ; but chose to surround the

ess Cont ' nuec t chains of iron. Upon this principle,lihi 8es • s C ' la ’ n was provided for each of the two floor>di Wn 66 ^ ate IV* Figure 7. The bars composing theljj»t b 6 j one ’nch and a quarter square, that the most iront 0 . - cant , ded in a given space, the corners only were aMi ei ‘> th ’ an( t the double parts being brought nearjg gg c Whole was comprehended in a groove, of some-th 0 ''’hich t , ari f °ur inches wide, and as much in depth ;ejjtch, t] l0 le chains being introduced and brought to aiO togjj !: e st of the cavity was filled with lead, of whichft 0 ,°d. Th 0Ut e ^ even hundred weight, in the followingh)e s ) e chains were oiled all over before they came

and the circumference of the groove was

t s ' 10r e ;

* into fVv *

% i frorv 1 OUr P arts hy stops, or dams of clay, to preventof j rQ Rowing farther than one quarter at a time. A\ '°Usly a Settles were provided, capable of melting com-\,^ a n ti r! n fun* six hundred weight of lead each ; and\ e ' v brtt jj ^ Was brought in each to a full red; that is,a tei than we used for the cramps, as the iron oftw 'ty ’p ® well as the stone, were cold. The whole!St ’ a M t] 68 ^ being brought to a heat that we judgedto be Stn e quarter-groove being supplied with oil sufli-\ bri s t?i ar tbe whole surface, two persons, with each aHi tl/ 16 qua / aS tbe y could, poured the melted metal intoN lead h 6r ^ le S roove ; and, as soon as it was full,‘e ai e K e j= an to set, one of the clay dams was removed,e u hot metal was poured upon the end of the

former mass, till it was perceived to re-melt and unite withthe fresh metal. This done, the dam at the other end of thefirst-run mass was taken down, to prevent its cooling morethan was necessary, and the third quarter was treated likethe former ; the end of the mass rendered solid by cooling,being re-melted by the fresh hot metal : lastly, both theremaining dams being taken down, and the metal at each endhaving a considerable heat, it was found practicable to dis-solve both the ends of the former masses ; first applyingboth ladles to that which had had the greater time to cool, andafterwards to the less : by this means the whole was broughtto a solid consistence, and the chain entirely buried in thelead. It is, however, to be remarked, that to preserve properimpressions in the lead, for the joggles of the course above,those impressions were made by confining down bricks inproper places, which, when removed, the proper marblejoggles were set with mortar in their places.

“ Monday, October 2, we proceeded to set up the centre,composed of sixteen ribs, (see Plate VIII. Figure 3,) forputting the floor together upon ; but the weather continuedbroken till Saturday, the 7th, on which day the Eddystoneboat came out, having on board the roof, or platform, forcovering the building, and protecting it from the entrance ofthe downfall spray; together with the doors, iron-work, andtimber for fitting up the same for habitation. This afternoonwe landed, and went on with the setting of the outwardcircle of floor-stones, made the holes in the wall for fixing thehinges of the entry and store-room doors. In particular, Icaused the middle stone to be laid upon the centre, by way ofweight, to keep it steady. Three of the four stones thatwere to connect with the centre-stone were laid upon the topof the wall, on the north-east side : and the fourth I causedto be hoisted and suspended upon the triangle, in the posturethat is shown Plate VI. at stage second. So that the triangle,which was all of it completely within the area of the top ofthe building, would be kept down by the weight of this stone,which was between seven and eight hundred weight. Theother three that lay upon the wall, I caused to be carefullydrawn within the circumference thereof, so that there mightnot be the least projecting part for the water to strike againstin flying upwards ; which I judged quite necessary, thoughthe walls were then upwards of forty-three feet above thefoundation-stone, and near thirty-five feet above the top ofthe rock.”

The weather now set in so bad, that no farther operationsof consequence took place that season. On the 10th ofOctober, Mr. Smeaton was mortified with a copy of a reso-lution of the Trinity-Board, declining his proposal of exhibit-ing a light that winter upon the foundation of the building.

“ During my stay in London , in the early part of the year1759, I received regular accounts of the proceedings at MillBay, which were carried on with all the dispatch I couldwish ; but the weather having continued unfavourable tovisiting the works at the Eddystone during the winter, I gotno report thereon till I received Mr. Jessop’s letter, dated the27th of March, wherein he informed me that on the 21st ofthat month, being the first opportunity he could catch afterthe violent storm which had happened on the 9th preceding,they found not only the solid, but the hollow work perfectlysound and firm ; all the mortar having become quite hard ;and, in short, every part of the work in the situation in whichit was left by the workmen in October: the only derange-ment was, that the sea had carried away the south fenderpile from the rock ; and also, from the top of the wall, one ofthe three stones that I had taken care to draw within theverge of the circumference of the wall, as mentioned. Theyhad found the fourteen pieces of stone set in the circum-

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