Mr. White's Design for the Nev) London Bridge. 183 



city, although the exact amount was not numerically ascer- 

 tained. This specimen was preserved unbroken. Upon the 

 whole, however, it has the advantage of the oaks in strength, 

 except those marked No. 7 and 8, which were remarkably fine 

 specimens; but it will be found by referring to Barlow's Essay 

 to greatly exceed the strength of oak in general. 



The results of the oak experiments seem certainly to be in 

 favour of the fast grown. " These experiments, " Mr. Wi- 

 thers observes, '" throw new light upon the subject, and lead 

 to the most important conclusions. They prove not only that 

 fast growing timber is superior in quality to that of slower 

 growth, but that by the constant application of manure to the 

 roots of trees planted even in good soil, nearly double the 

 quantity of timber may be obtained in the same period, while 

 its strength instead of being diminished will be thereby in- 

 creased." 



XXIV. Papers relating to aDesignfor the Neiv London Bridge, 

 on the Principle of Cementitious Architecture : — exhibited to 

 the Committee of the House of Commons, on the \Uh of April 

 ]823. By John White, Esq.* 

 [With a Plate.] 



Contents.— Mr. White's Letter to the Comptroller of the Estates of 

 London Bridge.— Mr. Newman to Mr. White.— Mr.White to Dr. Gre- 

 gory.— General Observations on the Designs for London Bridge. — Dr. 

 Gregory's Reply.— Dr. Gregory's Observations.— Mr. White to the 

 Editor of the Quarterly Journal. — Account of Experiments on Ce- 

 ments. — Inference fiom these Experiments. — Extract from the Me- 

 moirs of Savary, Duke of Rovigo. 



I. To the Comptroller of the Estates of London Bridge. 



Sir,— 

 BEG leave to submit to your notice the following sugges- 

 tions upon the subject of the removal of London Bridge, 

 to which tlie mind of the public is at the present time so much 

 directed, premising that I agree with the Second Report of the 

 Committee of the House of Commons, that a work of such 

 public importance as the plan of ISli should not be under- 

 taken without the greatest and most unequivocal certainty of 

 ultimate success, and that it is, as the Committee conceived, ex- 

 tremely doubtful whether a New Bridge would not ultimately 

 be found less expensive than the proposed alteration. 



The River Thames is considered as a river having an arti- 

 ficial obstacle, producing a rapid and extremely irregular fall 



• Communicated by the Author.— Mr. Telford's Report, in \H-2',\, on the 

 cfTccls on the Thames of reiiuilding Loniion Bridge, and another paper on 

 tiie same subject, will be found in Phil. Mag. vol. Ixii. p. iJl,28. 



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