4S 



THE CIVIL ENGINEER AND ARCHITECPS JOURNAL. 



[Feb. 



resistance, and consequently diminished total pressure required), and there is 

 no reason whatever why any required strength may not he given to these 

 parts; so that if there should he apprehension from the unequal action of 

 the piston when e.vpansion is used, the strength may he increased at plea- 

 sure. Can the gradually diminishing force of the steam of an expanding 

 engine do more misctiief than the great shock which must occur in low. 

 pressure engines, owing to their increased resistance ? Then every one 

 knows what sudden concussions are produced throughout the machinery of 

 a condensing engine at the moment when the air. pump discharges its con- 

 tents, at wliich instant the whole pressure of the atmosphere is suddenly 

 thrown upon the area of the pump." 



The parenthesis in the above extract involves a serious error. Even sup- 

 posing we admit the " prejudicial resistance," and consequently the " total 

 pressure," to be less in the high-pressure than in the low-pressure engine, it 

 by no means follows that the strains of the individual parts are diminished. 

 Those strains arise not merely from the external resistance, but also from 

 the momentum of the working parts — or, to use mathematical language, 

 they depend upon both the eft'cctive and impressed forces. For instance, a 

 grindstone, though suffering no retardation from the friction of its axle, 

 might revohe so fast as to be torn to pieces by its own centrifugal force. 

 Similarly, the parts of a steam-engine may move backwards and forwards so 

 fast, as to be fractured by excessive strains : these molecular strains being, 

 moreover, far more dangerous where the motion is reciprocating than where 

 it is rotary. 



With respect to friction and attrition, also, it is undeniable that both 

 increase with increase of velocity. If a drill, for instance, revolve slowly on a 

 plate of steel, it will make no impression — if it revolve very fast, it will wear 

 away a hole for itself immediately: the same considerations apply to the 

 rubbing parts of steam engines. The review has, however, already extended 

 to such a length, that we must not at present pursue the subject any further. 



The Life o/James Gandon, INI.U.I.A., F.R.S., Architect, icilli Original 

 Notices of Contemporary Artlsta ond Fraijmenls of Essays, From ma- 

 terials collected and arranged by his son, James G andon. Prepared for 

 publication by the late Thomas Wulvany. Dublin: Hodges and Smith. 

 1840. 8vo. pp. 2'J7. 



Gandon, though an Englishman by birth and education, executed the 

 greater part of his architectural v\ork3 in Ireland. Those by which he is 

 best known are the Custom House, Courts of Law, and King's Inn, Dub- 

 lin. 



He evinced early in life a strong predilection for mathematical and en- 

 gineering drawing — pursuits for which some of the roost celebrated archi- 

 tects have exhibited great aptitude. His professional career commenced 

 under Sir Milliam Chambers, from whom he acquired, besides his archi- 

 tural knowledge, a vast stock of general information : for his preceptor was 

 a great traveller — born a Sweede, he had travelled much in the East, 

 visited China, and wrote a book on its architecture — had resided several 

 years in Italy, and minutely informed himself respecting Roman architec- 

 ture. Gandon began life well : greatly to his preceptor's gratification, he 

 obtained the first cf the architectural medals given by the Koyal Academy. 

 This achievement took place in 1709, the year after that body was in- 

 stituted, and is described in the following terms : — 



" As soon as I read the advertisement for the distribution of these pre- 

 miums, I was like a person electrified. I hurried to my friend Paul Saad- 

 by, who soon assured me that I could have no chance of success as a com- 

 petitor for the gold medal in architecture, inasmuch as I uas i.ot elegible 

 to be a candidate: the advertisement requiring that all the candidates 

 should be students of the Koyal Academy. This restriction certainly ap- 

 peared a formiiiable obstacle to my becoming a competitor on the occasion. 

 1 had not much time fur reflection, and the temptation was great, but I soon 

 determined how I should act : 1 immediately entered my name as a student 

 of the Academy, and attended all the lectures given by each professor. 

 This was my only alternative. 



"The Academy gave ample time for the candidates to prepare their 

 respective productions. I commenced instantly to arrange my ideas on 

 the sul>Ject given, which was a triumphal arch, commemorative of the 

 Seven Years' War. 



"The day at length arrived when the candidates were to send in their 

 designs, and I was soon informed, to my very great gratification, that my 

 design was declared the best, and that, consequently, I should obtain the 

 gold medal. 



" On the day fixed for the distribution of the medals, but before they 

 were actually delivered, the architectural class were required to attend a 

 Committee of the Academicians in a private apartment, in order to test 

 tliPir respective powers in impromptu composition. TliedilTerent subjects 

 were deposited in a vase, out of which each candidate drew his envelope , 



in which the subject was written. That which came to my hand was a 

 park-gate, or rather an ornamental entrance to a park. Having first ar- 

 ranged my ideas, I then sketched out my design, and it was more admired 

 by the Committee than my triumphal arch. 



" When the medals were being distributed I was congratulated by many 

 of the members, but particularly by Sir William Chambers, who expressed 

 the pleasure he experieuced on finding his pupil so early distinguishing 

 himtelf." 



Gandon next obtained the second of the premiums offered by the mer- 

 chants of Dublin for a new Royal Exchange, and it appears from the bio- 

 graphy that the award of first premium was influenced by private interest 

 — a circumstance by no means unparalleled, as (we doubt not) many of 

 our readers could attest. The next premium gained by Gandon was one 

 of 100 guineas for the "new Bethlehem Hospital." This was the last 

 public work for which he competed in England. 



In 1779, he received an invitation from Lord Carlow to go over to Ire- 

 land, which he accepted, and was then appointed architect of the New 

 Custom House. They manage matters in Ireland in a manner peculiar to 

 themselves, as Gandon found out to his cost : for on his arrival, the opposi- 

 tion of individuals to the removal of the Custom House had become so 

 strong, that it was actually necessary that he should secrete himself for 

 several months. The foundations of the new building had scarcely be«n 

 commenced before the mob were instigated to destroy the fences surround- 

 ing them. The architect received letters threatening him with personal 

 injury, and in consequence always visited the works with a good cane 

 sword ; and " having been in early life a good swordsman (says he), I 

 am determined to defend myself to the last." There were other difliculties 

 however besides those of a personal nature. 



"The labourers had scarce got down two feet below the surface when 

 they came to water, which four men emptied with scoops as they continued 

 to extend the line of trenches, which were carried on in short lengths, and, 

 for convenience, of difl'erent depths. It became necessary to make dams 

 across parts of them with sods, and to empty the water from the lower to 

 the higher dam, until it was at last sent ofl'inadrain prepared for that 

 purpose, our pumps not being then ready. The ground was opened first 

 at the north and continued round to the east front ; then to the south end, 

 where a boiling spring with sand appeared at about four feet below the 

 surface, which filled up as fast as it was cast out. It extended for a con- 

 siderable distance. Inch and half sheeting piles, about seveu feet long, 

 were driven down with a maul, to keep up tlie bank, and sods were fitted 

 in layers between it and the piles, which preveuted the sand from being 

 washed out, thereby enabling the men to clear out the trenches to the depth 

 required. The general texture of the ground was gravel, mixed in some 

 places with a layer of blue clay and sand, under which was a hard strong 

 gravel. When the trenches were thus prepared and cleared out, the rough 

 masons then proceeded to carry on the first bench or course with all possi- 

 ble expedition with the black stone, and immediately filling in with earth, 

 in order to give less water to the pumps. In the ineaotinie another length, 

 and of the same depth, was got ready, and an additional number of masons 

 set to work. In this manner the whole was continued until all was brought 

 up to the level of the ground. 



" The quay wall or road on the south front was an old embankment, 

 made about the year 172;i ; it was sixty feet wide at top, and badly con- 

 structed ; the walls of black stone; its foundation laid on the surface of 

 the strand ; on the side next the river it was twelve feet high, but on the 

 inside only eight ; the tilling between the walls was a sand used for bal- 

 last ; the base of the foundations stood at least six feet above the bed of 

 the river; the tide not only soaked under them, but filtered in several 

 places through the joints of the masonry. It was, therefore, deemed most 

 prudent to commence with the north-east wing, after the portion of the 

 store-room, it being less liable to be incommoded with water from the 

 river. 



" Directions were now given for excavating that part of the centre of the 

 south front for the cupola and portico ; and as this advanced so near the 

 river we were certain of much obstruction from the flowing of the tide, 

 which was the only water that now gave us any trouble, for the springs 

 were now pretty well dried and kept under. The pumps hitherto used 

 were but thirteen or fourteen feet, we now used two of eighteen feet in 

 length. As the ground altered in its texture towards the river, becoming 

 more loose, with small sandy gravel, like that of the south-west angle, to 

 which depth we had sunk, we deemed it prudent to bore it in several 

 places which were near the angles of the front of the portico, but particn- 

 larly where the walls of the cupola were to be erected, to the depth of 

 eight feet below the then surface, and it appeared to be much of the same 

 sub.stance as that already described. A pile ten feet long and one foot 

 square was driven down in the centre to nine feet depth ; but after twenty 

 strokes of the ram it could be driven no further, which assured us thai we 

 had got down to firm ground. 



" Upon consulting with the principal artificers on the spot, it was thought 

 advisable to desist from sinking any more, but to make an artificial foun- 

 dation, in order lo sustain the great weight of the cupola ; but whether by 

 piling or otherwise was submitted wholly for my consideration. This part 

 I of the work had long occupied my thoughts, and to it I had given every 



