Calendar: 1885-1886 Page 701

APPLIED SCIENCES 693 Sketch longitudinal section of locomotive boiler showing the fire box smoke box and the positions of the safety valve regulator valve and blast pipe Explain how draught through the grate bars is obtained by the action of the exhaust steam Make sketch through the cylinder and steam and exhaust passages of double-acting engine worked by drop valves Show their position and explain how they may be worked The diameter of cylinder of horizontal engine is 15 inches and the pressure of steam 20 lbs on the square inch the length of the crank is foot and that of the connecting- rod feet find the thrust along the connecting-rod and the pressures on the guide bars when the crank is vertical In double-acting condensing engine the absolute steam pressure is 45 lbs per square inch The steam is to be cut off at half stroke and the point of release and of compression are to be from each end of the length of the stroke the back pressure is to be lbs on the square inch Sketch ap proximately the indicator diagram which would be given by such an engine and explain the method of setting the eccentric constructing the slide valve and computing the power of the engine In marine engines with large cylinders it often becomes necessary to diminish the travel of the slide-valve while keeping considerable opening of the ports for the admission of steam Sketch section through valve and ports show- ing how this can be done and put the valve in its position at the commencement of the stroke of the piston FIRST YEAR Describe the process of blowing and flatting sheet glass How is its thickness specified Sketch mould and deckle employed in the manufacture of paper by hand and explain how the apparatus is used in