EXPLANATION OF THE PLATES. 



385 



INDICATOR DIAGRAMS, 



SHEWING THE PERFORMANCE OF THE ENGINES ON BOARD THE WILBERFORCE DURING A VOYAGE 

 BETWEEN LONDON AND HULL, ENGRAVED FROM THE ORIGINAL CARDS. 



DIAGRAM, No. 1. 



15-35-2=13-35; 13 ' 35X2827X252 =288-2 Horses' Power. 



33,000 



!? 



o 2 

 a 3 



n> o 



o= 



t 



V 



W-7 16-8 W8 16-9 



IT- 



W- 



Pressure of Steam in Boilers, 11 inches of Mercury. Revolutions, 21. Condenser 



Gauge, 29-5. 2h. 30m. P.M. 



Taken at the Nore from London to Hull. April 7th, 1838. 



DIAGRAM, No. 2. 



16-54 - 2 = 14-54 ; ^4X2827X228 = 283 . 6 Horses - p ower . 

 33,000 



Pressure of Steam in Boilers, 13-5 inches of Mercury. Revolutions, 19. Con- 

 denser Gauge, 29-5. llh. 30m. P.M. Abreast of Winterton. Wind, N.W., blowing 

 very hard. Considerable swell, Vessel rolling, Gib and Fore Sails set. 

 From London to Hull. April 7th, 1 838. 



3 c 



