370 



Till] CIVIL ENGINEER AND \UC1I1TE(JTS JOURNAL. 



[October, 



have been expected to be a. treatise interesting only to a very few), 

 whereas it may be considered as a historical woi'Ii, and one too of a 

 novel and most interesting description. 



In the same way the most inveterate boki ifunns, although they 

 iustlv give the preference to an original binding, never hesitate if a 

 book is dirtv, " soiled or sullied," or has an irreparably "frail" or 

 tashed binding, to get it cleaned and reinstated in a vellum, Russia, 

 or such other binding as most befits the date and nature of the work. 



Although the best authorities therefore are clear as to coins and 

 books, I do not think the same feeling exists with regard to the repair 

 of ruins, although I cannot bid, think that all the three cases are 

 parallel. 



To dcstrov the picturesq\ic eliect of an old .d)bey or church, seems 

 generallv to be considered as a sort of murder of antiquity, the atrocity 

 of which no inducement can palliate. Altliough it is impossible to 

 deny that a disnumlled tower may have a more pictiu'esquc ett'ect at 

 a distance than if it were entire, and a'so that shattered masonry does 

 frequently assume a romantic outline which is no where else to be 

 found, still a complete building may have in some degree a picturesque 

 as well as architectural outline, and these advantages, when combined 

 with that of ])erpetuating the perfection of the design to future ages, 

 and its restored utility, are, I think, quite enough to warrant judicious 

 restitution. 



I need hardly say that I do not apjirove of such Vandalism as to 

 complete an imperfect building in a diti'erent style of architecture from 

 the original, as may be found in LlandaH' cathedral, where the alte- 

 rations, as lar as I recollect, are in the Grecian order, which contrasts 

 wretchedly with the original. 



The most interesting spot in the three kingdoms I take to be West- 

 minster ^Vbbe}-, imd I am sure all will agree that were that building 

 allowed to fall into a ruinous state. — to lose its roof and so forth, it 

 would not in any way possess the same interest. When we enter a 

 reritablt riin, destitute of all the minor details wdiich it once possessed, 

 we have to cause with ourselves in order to awaken a suitable interest, 

 and after all, that interest cannot but fall short in intensity of that 

 which we at once and irresistibly feel on entering an ohl richly deco- 

 rated cathedrd, with its curiously carved oaken stalls, its lofty roof, 

 and all the other adjuncts of an ancient "building, which the storms of 

 troublous times ha\ e not yet swept away from our view. And this is 

 what makes the cathedrals and religious houses of England triumph 

 so much in interest over similar buildings in Scotland, where the tire 

 of intenqierate zeal has, in too many instances, left its records in shat- 

 tered pillars and broken walls, the wrecks of glorious sjiecimens of 

 architecture. How tenfold interesting, if entire, woulil have been the 

 cathedrids of Melrose, Dryburgh, t-t. Andrews, Aberbrothwick, Elgin, 

 lona, and many more, where now enough only is left to show us hum 

 much we have lost. And if no new interest and opinion is formed on 

 this subject, we shall, I fear, find such relics grow gradually less inte- 

 resting. Every blast adds to the rubbish, and every winter curtails 

 their extent. 



The object I h.ive in view in these remarks is to waken, if possible, 

 such an interest in ruinous churches, as shall deterndne those >eho have 

 an inHiance in the erection of new churches, rather, wlicn possible, even 

 although at a much greater cost, to kkstoisk old o:\es than build nkw. 

 What gave rise more immediately to the preceding remarks was a 

 visit to the island of lona, vvhere the Duke of Argyll, with his charac- 

 teristic benevolence, has recently erected, and i believe endowed, a 

 church, which, howevei-, cannot be said to possess the slightest claims 

 to architectural eliect. In such a case, then, how much more suitable 

 would it have been to have restored (with proper advice) part, if not the 

 whole, that remains of the ancient cathedral, which St. Coluraba 

 erected soon after his arrival at the island in A.D. 5(33, and which was 

 so miserably ransacked at the time of the Reformation, whereby .Scot- 

 land lost her " ancient annals and MSS." (vi'hich were kept at lona, 

 " in hidden presses of the church,") and "large parchments signed by 

 the king's own hanils, and sealed either with seals of gold or wax."* 



I trust that these remarks wdll at least get a little consideration 

 from those to whtan they are more especially addressed ; and should 

 it happen, as in many instances it may, that no drawings are in exis- 

 tence to shew the original plan of a building now much dilapidated, 

 the best course is to take the advice of some architect who is tho- 

 roughly acquainted (as every one should be) with the styles of archi- 

 tecture which distinguished dillerent ages, and with this advice to 

 complete the building in keeping with those parts which still remain. 

 In conclusion I may be pernntted to observe, that although 1 have 

 no doubts as to the orthodoxy of the general principles herein advo- 

 cated, I am nevertheless willing to admit that many specio\is and even 



* Sir George Mackenzie, Def. of Roy. Line of Scotland. Lend. 1685, p. 30. 

 Traii^l. of I'aiilus Jovius. 



reasonable objections may, in particular cases, be brought forward — 

 nay more, I allow that even in the case of lona, I may have formed an 

 erroneous o|iinion, as I had not time, during my visit, to examine 

 either the old cathedral, or new church with that degree of care 

 which, had my time permitted, I should have done. 



^ipt. 10, 1S39. L. 



BUNNETT AND CORPE'S CONCENTRIC STEAM ENGINE. 



SiK. — Referring to the June and July numbers of your valuable 

 Journal, I beg to dissent from the conclusions you have draw u, rcsjiect- 

 ing the merits of Messrs. Buunett and Corpe's Concentric steam 

 engine. 



I am not disposed to deny the accuracv of the fables you have 

 given; the results noted therein, might naturally be expected from the 

 manner in which the relative powers of the new, and old modes of 

 application were decided; my object is to show that one main feature 

 in the case has been overlooked, which, when taken into account, will 

 considerably diminish, if not altogether do away with, the advantages 

 which at first sight appear in favour of the Concentric engine ; for 

 whatever additional jjower is exerted by it, a corresjiouding expense 

 of steam will be the necessary consequence, which is tantamount to no 

 advantage at all. 



If this can be shown to be true, I am humbly of opinion that it can- 

 not be claimed for this machine, that any power is gained by its adop- 

 tion, as we are only entitled to consider tliat we have gained power 

 by new combinations, when these enable us, at the same expense, to 

 produce greater elf'ects than v\'ith the old. 



In the Concentric engine there is nothing new in |ninciple ; the 

 arrangement of its parts diiiers little, and that only meclianically, from 

 those at present in use. Desirable as it may be, and often is, to 

 modify the mechanical powers, to suit the various purposes of ma- 

 chinery ; all the changes we can ring upon them will never help us to 

 an increase of power, beyond the lessening of friction through sim- 

 plicity of construction. 



In order to illustrate what is meant by these remarks, let me call 

 your attention to the annexed diagrams, which are nearly similar to 

 those in the last number of the Journal already referred to : — 



Fig. 1. 

 Representing the new mode of applying the power. 



A the annular piston roil, B the ci imnctuig rod, C' the crank, V the pislon 



Fie. 2. 



Mg. 



Representing the old mode of applying the power 



I) the piston rod. K llic cunneciing ri.d, F the crank, cnual to the crank C. 



It is evident, from the construction of these diagrams, that the 

 annular piston-rod A, will move through a greater space than the i)is- 

 ton-rod D requires to do, in producing re^ olutions of their respective 

 cranks, C and F. The stroke of the "piston D will be as the length of 

 the straight line I I, or as the lines K K and L L, these three lines 

 being equal to one another. On the other hand, the stroke of the 

 annular piston-rod A will be as the curved line K <j K, which is nuich 

 greater than the straight line K K. 



Now assuming that the impulsive force is a constant quantity, and 

 alike at each instant on both pistons, it follows from the above, that 

 the effects on the cranks will be respectively as the length of the 

 curve K G K is to the straight line K K ; in other words, the length 



