No. 133.] 75 



2. By placing within this condenser a system of tubes, into 

 which the steam flows from the cylinder, and in which the vacuum 

 is maintained by a smaller and separate pump, specially applied 

 to this object. The water drawn o£F by this pump, is alone used 

 in feeding the engine, while the water used in the outer condenser 

 runs to waste. 



Evidence has been laid before the undersigned, which has es- 

 tablished the fact, that a condenser of this construction, has been 

 in use, without accident, for a number of days, far exceeding the 

 usual passages of marine steamers ; that a partial defect in the 

 tubes did not impair, in any way, the absolute efficiency of 

 the engine; that such partial defect did no more than diminish 

 the saving of fuel, which was the result of the use of the appa- 

 ratus when in perfect order; that such partial defects are readily 

 repaired, by tlie means, at the disposal of the engineers of the 

 steamers. The advantages which this condenser presents to steam 

 navigation, are, therefore : the saving of a large proportion of 

 the fuel, that is required when the boiler is fed by sea water, by 

 an apparatus, which, at worst, will not, when out of order, in- 

 volve the consumption of more fuel than would be necessary with 

 the common condenser ; and the great prolongation of the dura- 

 tion of boilers by feeding them with pure distilled water. 



The undersigned, thierefore, in consideration of these advan- 

 tages, by which the cost of steam voyages may be reduced, their 

 length increased, the capacity of cargo enlarged, the duration of 

 the apparatus prolonged, recommend, that a gold medal, of the 

 highest order, be conferred on Mr. Pirsson,.by the American In- 

 stitute. 



A^'exc-York, 2\st October, 1852. 



J. W. AYRES, 

 JAS. RENWICK, 

 H. R. DUNHAM, 

 HORATIO ALLE^f, 



Judges. 



