AMERICAN INSTITUTE. 697 



for publication in tlie Transactions of the Institute, and that 

 members who participate in such discussions deliver to them 

 concise written papers of their remarks. Carried. 



Mr. Johnson read a letter from Mr. Jonathan Amory, of Boston , 

 presenting his pamphlet on steam for consideration. He has many 

 years' experience on that subject. 



Mr. \Vm. A. Garbett, of Roxbury, presented an improvement 

 in locomotive boilers. Referred to a special committee to be 

 appointed by the Chairman. 



The Chairman called up the regular subject : 



ECONOMY OF HIGH PRESSURE STEAM. 



The Chairman remarked that high pressure steam works best 

 at the pressure of 100 lbs. per square inch. 



Mr. Stetson — They use very high steam on our western w^aters, 

 even as high as 1,000 pounds per inch, but heating steam very 

 high destroys its expansibility. For instance 1,200 degrees, and 

 the water red hot, do not answer. Let us take but a short step 

 and say truly, that he who can produce an engine which will 

 save but one per cent of steam, will render to the world a great 

 service. He then explained the economy of the several steam 

 cut offs. 



Mr. J. K. Fisher observed that Jacob Perkins worked steam at a 

 pressure of 1,500 lbs. per square inch! He explained Wolf's & 

 Perkin's arrangement of cylinders, and cut off. He approves 

 some of the cylinders now in use, for two for each propeller, using 

 high pressure steam, and by an exhaust, using that steam twice. 



Mr. Reynolds could not discover the propriety of that two 

 cylinder and exhaust arrangement. 



Mr. Cohen — How can the pressure be kept at 6 lbs. in the 

 receiver 1 



Mr. Fisher said it would vary according to different arrange- 

 ments of the cut olFs. 



Mr. Reynolds — In the boats on St. John's river, there are two 

 cylinders used with economy, less steam but more steadiness. 



