TRANSACTIONS OF SECTION G. 891 



almost mathematically correct and giving equal leads, ports, and points, if cut off 

 for both ends of the cylinder, at the same time that it gives a much, more rapid 

 action at the moments of admission, cut off, and release than is usual with, the 

 back gear ; while the machinery for attaining this result is less costly and less 

 complicated than by any of the ordinary methods. This consists of a lever attached 

 at its longer end, through a parallel motion, to the connecting-rod about midway, 

 the fulcrum of that lever sliding in the direction of the vibration of the connecting- 

 rod, in a curved path, which can be angled to either side of its centre line. From 

 the outer and shorter end of this lever a rod is taken direct to the valve-spindle. 

 That part of the movement of the valve due to ' lop ' and ' lead ' is effected by the 

 action of this lever as a lever, and the movement required for port opening is 

 imparted by the sliding of the fulcrum of the lever in the curved path ; and accord- 

 ing to the angle given to this path, forward or backward motion, or any degree 

 of expansion, is given. 



Since its introduction in 1880 this gear has been applied and tested on almost 

 every kind of steam-engine. For locomotives, especially for express work, it has 

 done good service, many of such engines having already run heavy mileages, while 

 doing very high speeds, and witli lighter repairs than the ordinary types of engines. 

 Also for marine engines, from the smallest launch engine running 600 to 700 

 revolutions per minute, up to the ponderous engines of war-ships running up to 100 

 revolutions, and indicating upwards of 5,000 horse-power, it has been applied with 

 success. It is also being built for even larger sizes, where the aggregate indicated 

 horse-power in each ship will be 10,000 horse-power. 



The distribution and treatment of the steam in the cylinder, as shown by the 

 indicator cards from such engines, is all that could be expected from the peculiar 

 action imparted to the valves ; and the continued endurance and freedom from 

 repairs promise a continued adoption of this new system. 



On Heating Buildings by Steam from a, Central Source. 

 By J. H. Baktlett. 



SATURDAY, AUGUST 30. 



The Section did not meet. 



MOXDAY, SEPTEMBER 1. 

 The following Papers were read : — 



1. On the Lighthouse System of Canada. By William Smith. 



In Canada, no light dues are exacted from shipping, and the cost of maintaining 

 the lighthouses is a direct charge on the general revenue of the Dominion, and is 

 provided for annually by a vote of Parliament. 



During the fiscal year ended June 30, 1884, the total cost of maintaining the 

 549 light-stations in Canada, with the fog-signals, buoys, and beacons, and four 

 steamers required to attend on the light service, was #541,'291. 



The system of free lights was adopted by the public men of Canada with the 

 view of reducing the charges on shipping trading to the St. Lawrence, and thereby 

 cheapen freight by this route. By adopting this policy, the shipping and forward- 

 ing interests of Canada have secured a fair share of the carrying trade of the West, 

 a large portion of which, however, finds its way by New York" and other United 

 States routes. 



