in the screen-wire packing, lay ready to be picked up 

 by the incoming air charge as it passed from the 

 receiver to the working cylinder. Thus, Ericsson 

 maintained, the caloric could be used over and over 

 again. The furnace was needed only to supply the 

 inevitable losses of caloric by radiation and by the 

 "heat lost by the expansion of the acting medium." ^ 

 How simple the idea appeared, and how attractive ! 

 Its implications were not clear to Captain Ericsson, 

 but it will be found that the errors into which he fell 

 were not yet plainly marked or easily explained. On 

 the other hand, a substantial number of engineers and 

 others recognized intuitively that he was, in fact, 

 pursuing a will-o'-the-wisp. 



The Trial of the Ericsson 



The trial voyage, on Tuesday, January 11, 1853, 

 was expected to supply the definitive answer to the 

 questions and speculations that had been accumu- 

 lating while, over a period of a year or more, the ship 

 and her engine were being built. The information 

 that had been parceled out to the press by Captain 

 Ericsson concerning the caloric engines was accepted 

 for the most part uncritically, and the community at 

 large was prepared to see a revolution in power-plant 

 practice take place in the protected waters of New 

 York Bay. 



An assemblage of perhaps 60 people was invited to 

 be present. Editors or reporters of all the New York 

 dailies. Freeman Hunt of the Merchants^ Magazine, 

 and, according to the New-York Daily Times, "a few 

 gentlemen whose scientific abilities render them amply 

 qualified to pronounce judginent upon a project 

 fraught with such momentous results" * were taken 

 on board the Ericsson at the Battery. One of the 

 scientific gentlemen, Prof. James J. Mapes, consultant 

 on brewing and agricultural chemistry and good 

 friend of the inventor, was present as speaker at the 

 sumptuous banquet that was to crown the festive 

 occasion. 



There was, however, one uninvited guest. Orson 

 Munn, the 28-year-old editor of Scientific American, 

 slipped on board unnoticed '' and sounded the only 

 jarring note in an otherwise solid and harmonious 

 chorus of praise. Munn, a patent solicitor who used 

 his paper's columns to promote the inventions of his 



5 U.S. Patent 8481, November 4, 1851. 



8 New-York Daily Times, January 12, 1853. 



' Scientific American, }a.mia.vy 22, 1853, vol. 8, p. 149. 



Figure 3. — Patent drawing of Ericsson's caloric 

 engine, 1 85 1 . (From Mechanics'' Magazine, 

 London, July 19, 1851, vol. 55, p. 41.) 



clients, had not been invited for the reason that 

 Captain Ericsson could hardly expect fair treatment 

 by him, because Ericsson was not Munn's client. 



The harbor of New York was, as usual, a busy one. 

 There were coastwise and harbor sailing craft, clippers 

 bound out for California, transatlantic packet ships, 

 and, as if to proclaim that the age of steam was here 

 to stay, the Collins liner Baltic thrashed her way past 

 the Ericsson at her usual 14 knots. ^ 



The trial voyage took the Ericsson from the Battery 

 to a point ofi" Fort Diamond (now Fort Lafayette) 

 in the Narrows, about 7 miles distant, and return. 

 The ship was under way for about two hours and a 

 half. 



A well-planned program — one journal, whose 

 editor was not invited, called it "a sort of 'sell' played 

 off on the reporters" ^ — kept the gentlemen of the 

 press occupied. There was a breakfast for those who 

 had been hurried by the early hour of departure, 

 and wine for those who had not. In the great cabin, 

 Captain Ericsson, using a pasteboard working model, 

 explained "in a very persuasive manner" how the 

 engine worked, and why. When they were not other- 

 wise occupied, the reporters could go down to the 



9 Scientific American, March 5, 1853, vol. 8, p. 197. 

 ' Appletons' Mechanics' Magazine and Engineers' Journal, May 

 1853, p. 117. 



PAPER 20: JOHN ERICSSON AND THE AGE OF CALORIC 



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