62 Transactions of the Amehican Institute. 



and resolution of forces. The governor, therefore, has perfect con- 

 trol of the valve, and the arrangement is remarkable for its simplicity. 



The Loomis engine has four independent valves arranged like 

 those in the Corliss engine. The valves however are conical, the 

 faces and seats being perforated with a number of openings. The 

 valves are operated by rods, connected to levers on the outer stem. 

 An eccentric on a vertical &pindle operates the exhaust valves and a 

 cam on the same spindle opens the steam valves which are closed by 

 springs. The advanced face of the cam is parallel to the axis of the 

 spindle, but the rear face is in spiral form. The cut off is varied by 

 the governor which raises or lowers the cam to allow the hemispheri- 

 cal ends of the operating rods to slip over the cam at different points 

 of the stroke. 



It was generally understood, at the opening of the exhibition, that 

 a test was to be made of the engines, but complete preparations 

 could not be made until the machinery was in position. 



Many of the exhibitors were very tardy so that the machine 

 department was hardly settled even as late as the first of October. 

 As the time was becoming limited in which to properly test the 

 engines, the chairman of the department of engines and macliinery 

 sent a note to the superintendent of the exhibition requesting him 

 to ascertain what means were available for making the trial and 

 report a plan of operation which could be carried out while judges 

 were being selected. A copy of this note, of the report made in response 

 thereto, and also of the approval thereof are each hereunto attached 

 and designated exhibits A, B, and C, preceding this report. 



In making preparations for the trials it was absolutely necessary 

 that no material interference be made with the exhibition. To 

 accomplish this required some little study. 



The engines were placed side by side in the machinery arcade 

 with wide passages between them, and as nearly as possible opposite 

 the main entrance from the larger building. Two lines of shafting 

 ran through the arcade, and a third parallel line was placed inside 

 the main building. The engines all belted directly on the first line, 

 which ran at 250 revolutions per minute. Tlie two other lines were 

 run at 140 revolutions. 



The receiving pulley of each engine was made with a clutch so 

 that either engine could do all the work, and allow the others to run 

 also, simply keeping their clutch pulleys in motion. 



There were two boilers of sufficient size to furnish steam for either 



