428 TRANSACTIONS OP THE AMERICAN INSTITUTE 



above the coal, from the doubling of the strata of conglomerate 

 rock and coal upon themselves. 



THE GREAT EASTERN. 



Mr. Fisher said that if the rudder had been suspended in the 

 centre, there would have been no twist, and it could have been 

 worked very easily. If the rudder had been put in the bow, the 

 screw might have been made four-tenths lower, giving it twice 

 the surface and therefore twice the power. This would be better 

 than employing two screws. 



The Chairman (Mr. Tillman). — The ferryboats have a rudder 

 at each end ; yet they always use that at the stern. 



Mr. Fisher. — Because the rudder is not suspended in the 

 middle ; and a rudder suspended behind the middle could not be 

 easily turned without better jStting apparatus than is generally 

 used upon ferryboats. If the rudder could be suspended entirely 

 above the water-line it could be keyed up better, and there would 

 be an advantage in that. It is stated the rudder part was of a 

 bad quality of iron. The Great Eastern has no keel, because 

 there is not room for one. As to her rolling, it will be well to 

 learn how her ballast was stored before condemning her for that. 

 I suspect that she had gone so smoothly in her earlier trips 

 that no pains were taken about storing the ballast. 



The Chairman (Mr. Tillman). — Mr. Cleveland considers her 

 the safest vessel that he ever made a voyage in. This storm 

 proved that she was very strongly built, for she did not tremble 

 at all. The Great Eastern is generally conceded to be a suc- 

 cess in one respect. The displacement of water is no greater 

 than if she were but half the length, and the friction along the 

 sides is .but little greater. I am informed that the Cunard com- 

 pany are now building a steamer 500 feet long. 



Subjects for Discussion. — The subjects selected for considera- 

 tion at the next meeting, are "The Crank Motion in Steam En- 

 gines," and "Instruments for the Culture of the Soil." 



STEAM CARRIAGE. 



Mr. Fisher exhibited a drawing of his steam carriage for 

 common roads. 

 Adjourned. 



