1840. 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



413 



It has been stated in explanation of the effect produced by my dilTu- 

 sion tubes, that as there is always plenty of air, or oxygen, in the 

 furnace, and a deficiency of heat, the introducing the air at a high 

 temperature, supplies this deficiency. This is directly the reverse of 

 what I have stated to be the condition of the furnace, and the flues 

 leading from it. The following extracts from my tract will put this 

 in a clear point of view. 



At page 124, I state, " The leading condition of the combustion of 

 the inflammable gases being the mixture with the oxygen of the air in 

 given quantities, and at a given temperature, those inventors have in 

 too many instances, to the utter neglect of the former, exclusively 

 directed their attention to the latter, — -the obtaining the highest de- 

 gree of heat, even to incandescence, for the gases. Now' this is un- 

 questionably the condition which demands the least attention on their 

 parts, if any at all." 



Again, page 129, " It is the palpable oversight of the distinction be- 

 tween increasing the faculty of combustion, and actually producing 

 that combustion, which has led to that manifest chemical blunder, — 

 the supposing that coal gas is to be btirmd by the act of bringing it 

 into contact with bodies at a high tenqierature : or, in the words of 

 the patentees, by ' causing it to pass through, over, or among, a body 

 of hot glowing coals.' In our efforts then, towards effecting the com- 

 bustion of the gaseous products of coals, it is essential that we steer 

 clear of this hitherto unquestioned practice : attending solely to the 

 question oi an, and all that has reference to its introduction, distribu- 

 tion, and diffusion: for we may take it for granted, that the condition 

 of heat is but a secondary condition ; and tliat the required tempera- 

 ture will never be wanting in the furnace, from the moment we ' light 

 ihejire,' if air be supplied in the proper quantity, at the proper place, 

 and in the proper manner: but if these conditions be not satisfied, an 

 accession of heat cannot remedy the evil, however it mav aggravate 

 it." 



I assert then, that there can be no greater fallacy, than su])posing that 

 giving a high temperature to the air admitted, can be the means of 

 effecting the combustion of the gases, or the prevention of smoke. An 

 analogy has been deawn between the effectiveness of hot air in the 

 manufacture of iron — this however bears no analogy with the intro- 

 duction of hot air to the furnace, as the means of effecting combustion 

 or preventing smoke. With your permission I propose considering 

 this point on a future occasion — at present I confine myself to denying 

 the assertion that my plan obtains any advantage from the circumstance 

 of the air being heated in its passage into the flues through the small 

 orifices of my diffusion or distribution tubes. 



I am, Sir, your's, &c. 



C. W. Williams. 



Liverpool, Nov. 20, 1840. 



THE NELSON MONUMENT. 



Sir — Since I last addressed you, the first stone of the Nelson Colmnn 

 has been laid, the work is progressing rapidly, and will continue to do 

 so until the public rise en masse to protest against so great an outrage 

 upon the principles of beauty, or, peradventure, the subscriptions be, 

 as at present, insufficient to complete the structure. We shall then 

 have a piece of a column, to show succeeding generations the lofty 

 standard of beauty amongst us, and to point out how we delight to 

 honour the great, the virtuous, and the brave. Shall we, the British 

 nation, permit this living libel to appear against our love of art; 

 glorying in the matchless works of our ancestors, shall we allow pos- 

 terity to point with derision to the evidence of their effect upon us. 

 Enough has been said to show that the Nelson Committee are alone in 

 their project, and it will be disgraceful, if the public submit to have 

 this column thrust upon them, in opposition to their better judgment. 

 Those journals in which we place most confidence in matters of taste, 

 the Athenaeum, the Literary Gazette, and the Art Union, have all pro- 

 tested against the proposed column; but despite this and the positive 

 opinion of the Select Committee of the House of Commons, the pro- 

 jectors pursue their object ^Jeryas aiit nefas, and the stone which Wel- 

 lington would have been proud to lay, is laid, with no public announce- 

 ment, and no popular enthusiasm, by the Secretary of the Committee. 

 We do not hesitate to say, despite the expression of condemnation 

 upon the whole building, that the portico of the National Gallery, ex- 

 hibits many architectural beauties in its internal columns, and the depth 

 of shadow caused by the projection of the antJE in front of the wall, 

 and it is the portico which the pedestal of the column will completely 

 hide. With all deference to one vvfiose opinion as to the good effect 

 in juxta-position of colossal, and ordinary proportions, demands from 

 all, the liighest respect, I would beg to notice that St. Peter's at Rome, 



has been objected to on account of the enormously disproportionate 

 figures lessening the effect of the architecture, and St. Paul's itself, for 

 the difference in size of its two internal orders. Sir F. Chantrey in 

 his evidence as to the effect of the column as an ornamental object, 

 says, "the Trajan, the Antonine, and the Napoleon columns are the 

 only monumental objects of this class that I have ever looked upon 

 with entire satisfaction ; I read the history of the man on the shaft of 

 the column, and thf mind is thus reconciled to see the statue so ele- 

 vated. I may be told we have not money enough for a work of this 

 character, that naval exploits furnish bad materials for sculpture, or 

 that the arts of this country are in too low a state to accomplish so 

 noble a work ; then I say, abandon the impossibility at once, and try 

 something more in keeping with our means and our genius." The 

 "general observations by T. L. Donaldson, Esq.," contain opinions as 

 to the bad effect of a naked column. If, therefore, it can be shown, 

 not that the funds do not suffice to enrich the shaft with bas-reliefs, 

 and crown the column with a statue of bronze, but that the subscrip- 

 tions are actually inadequate to complete the denuded shaft and the 

 perishable statue, and if in addition to these sufficiently cogent reasons 

 it can be proved, that a colossal column, when used without the struc- 

 ture of which it is as much a part as the leg is of the man, is an out- 

 rage against our most cherished principles of beauty, — it becomes the 

 people to prit^st lor.liy and speedily against the infliction of so great 

 a national indignity. 



I am, Sir, your obedient humble servant, 



A Lover of the Beautiful. 

 3G, Tollbridge Place, New Road, 

 November 20, 1840. 



ON COMPUTING EARTHWORK. 



Sir — Observing an article in your October number, page 334, on the 

 methods of computing Earthwork, by Mr. S. Hughes, in which the 

 writer asserts, that the tables of Messrs. Macneil and Bidder, " are 

 useful only for calculating sections where the scale is very small, and 

 where the heights cannot be taken otherwise than in feet — and that 

 where the scale is sufficiently large to show the heights in feet, and 

 decimals of a foot, they are of no use." I take the liberty of trans- 

 mitting to you tiie following for the purpose of proving that the tables 

 of Messrs. Macneil and Bidder, are as useful for such calculations, 

 where the heights are in feet and decimals, as in feet only. 



I have at present the tables of Mr. Bidder only at hand, although I 

 constantly make use of Mr. Macneil's for similar calculations, but an 

 example based on the tables of the former gentleman will be equally 

 illustrative of the use to be made of those of the latter. 



For my purpose I have selected the same example as Mr. Hughes, 

 in page 33[>. 



E.rample. — Suppose a piece of cutting or embankment 39"8 feet 

 deep at one end, and 24't) at the other end, the base or top 30 feet 

 and slopes 2 to 1, required the area, which being multiplied by the 

 length, shall give the true content. 



Mid. part. Slopes. 

 Intersection of columns 40 and 25, gives 79-5 and 2628. 

 '^■"" ■'■"- 39 and 24, gives 77 and 2471. 



Ditto 



ditto 



Difference 



2-5 and 157. 



Then '-— -^^ = -7, -7 X 2-5 = 1-75, 1-75 -f 77= 78-75 mid. part^ 



•7 X 157= 109-9, 109-9 -f 2471 = 2580-9 slopes. 

 Mid. part 78-75 x 30 =: 2362-50 

 Slopes 2580-9 X 2 to 1 = 5161-8 



Total contents in yards per chain 

 Then ^ X 9 = 3078-18 correct area. 



r524-3. 



In practice the last operation forms no part of the calculation, as the 

 lengths are taken out in chains and decimal parts. 



I remain. Sir, your obedient servant, 



Geo. B. W. Jackson. 

 Radcliffe Terrace, Gosmell Road. 

 Nov. 24, 1840. 



[The above is a very round about way for ascertaining quantities, to 

 say the least of it. — Ed.] 



