xviii LIST OF PLATES. 



PLATE EXPLANATION. 



PAGE 



XLIII., XLIV., XLV., XLVI. Elevation, plan, and two sections of the engines of the 



armed Russian steam ships Jason and Colchis .... 369 



XLVII., XLVIII. Hall's improvements on steam engines .... 370 



XLIX., L. Engines of H. M. steam ship Megaera ..... 378 



LI., LII., LIII., LIV. Engines of the Hull and London packet William Wilberforce 382 



LV. (A). Longitudinal section of Humphrys's patent marine engine . . 390 

 LV. (B). Longitudinal elevation of Humphrys's marine engine . . .391 

 LVI. (A). Midship section of the steam packet Dartford, showing a front elevation 



of a pair of Humphrys's engines ...... ibid 



LVI. (B). Plan of the engines of the Dartford ..... 392 



LVII., LVIII., LIX. Forty-five-horse power engine, constructed by W. Fairbairn 



and Co. ......... ibid 



LX., LXI., LXII., LXIII. Ten-horse power engine, constructed by W. Fairbairn and Co. 393 

 LXIV. Elevation of a locomotive engine, Stanhope and Tyne Railway ; constructed by 



Messrs. R. Stephenson and Co., of Newcastle-upon-Tyne . . . 394 



LXV. Section of ditto ........ 396 



LXVI. Safety valves of ditto ....... ibid 



LXVII. (A). Cylinder cover and connecting rods of ditto .... 397 



LXVII. (B). Cylinder and piston at large of ditto ..... 398 



LXVIII. Plan and section of boiler seating for a twenty-horse engine, at the manu- 

 factory of Messrs. Whitworth and Co., Manchester .' 399 

 LXIX. Messrs. Hague's double acting cylinder, with slides, &c. . . . ibid 



LXX. (A). LXX. (B). Sections of the engines of the Berenice steam vessel . . 400 



LXXI., LXXII. Beale's patent rotatory engine ..... 401 



LXXIII. Mr. Ayre's contrivance for preventing a locomotive engine from running off 



a railway ......... 403 



LXXIV. to LXXXIII. Relate to Mr. Mornay's paper on paddle wheels . Appendix 117 

 LXXXIV. to LXXXVIII. Sixty-five inch cylinder engine, erected by Messrs. Maudslay, 



Sons and Field, at Chelsea water-works ..... 404 



