134 



SCIENCE. 



[Vol. XIII. No. 316 



up, in shape of the inchoate eidolon-fori of some nameless dreamy 

 inventor. 



Technical journalism, in the field of electrical power at least, 

 would seem to be at a low ebb in New York. 



As for the current-generating plant and conductive system, they, 

 as well as the " Franklin," are entirely of the Daft design. The 

 former is on Fifteenth Street, about midway between Sixth and 

 Seventh Avenues, and wires of suitable size convey the current to 

 and fro between the stationary plant and the track-conductors. A 

 steam-engine of 250 horse-power drives four dynamo-generators of 

 50 horse-power each. 



The conductor is a copper rod, five-eighths of an inch in diam- 

 eter, sustained by insulators attached to the guard-timbers along- 

 side the track. Elastic copper " brushes " pressing against and 

 sliding along this rod convey the current to the electro-motive 

 mechanism, which it traverses, causing revolution by its passage, 

 and completes its circuit through the wheels and track-rails. 



Time and space will not admit of an analysis of the inherent and 

 incidental economy of electric propulsion ; but " he who runs may 

 read," whether or no the preference lies with the light, compara- 

 tively noiseless, cleanly electro-locomotor, devoid of steam, smoke, 

 cinder, and hot jets d'eau, or the ponderous, clamorous, steam- 

 locomotive, wasteful of fuel, destructive of road-bed, and inherently 

 hampered by nuisances from which its electric rival is absolutely 

 free. X. 



THE WORTHINGTON INDEPENDENT CONDENSER. 



That the practical results attained by condensing-engines should 

 approximate to those that theory indicates, it is important that the 

 condensing-apparatus employed should be the most efficient possi- 

 ble ; that it should maintain the highest vacuum, with the least cost 

 of production ; that it should be regular and reliable in action, and 

 simple in construction ; and that its application to the engine should 

 be unaccompanied by any risk of accident. These exacting re- 

 quirements, it is claimed, are fully met by the condenser shown in 

 the accompanying illustrations. 



Exhaust-steam from an engine enters a vacuum with a velocity 

 of about 1,900 feet per second; and water, under atmospheric 

 pressure, with a velocity of 47 feet a second. Excepting the ma- 

 chine herein described, it may be said that in all forms of jet-con- 

 densers operated by air-pumps, the injection-water and the water 

 from the steam fall to the bottom of the condensing-chamber, come 

 to a standstill before entering the pump, and consequently lose the 

 valuable momentum acquired when entering the vacuous space. 

 In this condenser, however, the construction and arrangement are 

 such that the momentum of the steam and water is conserved, and 

 this force is utilized to assist the pump in its work. 



By a careful adaptation of the injector principle, it is possible, in 

 an experimental way, to produce a vacuum, of low degree however, 

 without the use of a pump at all, — simply by the momentum given 

 to a flow of water by the impact of the exhaust-steam at the point 

 of condensation. A condenser dependent upon this alone is not 

 practical, because of its small range of action, the inferior vacuum 

 it obtains, and the low temperature of the discharge-water. A 

 change of the amount of steam to be condensed disturbs the theo- 

 retical conditions, and renders this kind of apparatus too unreliable 

 in practice. It is plain that the addition of a duplex pump to the 

 discharge of such an ejector condenser perfects and governs its 

 action. As the momentum of the water is not impaired, the highest 

 economy of operation is reached. 



In this condenser, the air set free by the condensation of the 

 steam is intermingled with the water. The pump has the same 

 regularity of motion that is characteristic of Worthington pumping 

 machinery ; in fact, it acts as a water-pump, although the water is 

 aerated. There is here a great distinction between this condenser 

 pumping aerated water, and an air-pump pumping air and water 

 unmixed. In the latter case, the air-pump has a varying and ir- 

 regular duty to perform, and the inevitable result is an irregular and 

 slamming movement. 



The lower of the accompanying illustrations is a longitudinal 

 section of one side of the condenser-pump, and also a section of the 

 condenser-cone, spray-pipe, exhaust-elbow, and injection-elbow, 



A is the vapor-opening, to which is connected the pipe that con- 

 ducts to the apparatus the steam or vapor that is to be condensed, 

 and in which a vacuum is to be made and maintained. The injec- 

 tion-water used to produce the condensation of the steam or vapor 

 is conveyed by a proper pipe attached to the injection-opening at B. 

 C is the spray-pipe, and has at its lower extremity a number of 

 vertical slits, through which the water of injection passes, and be- 

 comes spread out into thin sheets. The spray-cone D, by means 

 of its serrated surface, breaks the water passing over it into fine 

 spray, and thus insures a rapid and thorough intermixture with the 

 steam. This spray-cone is adjustable by means of the handle E. 

 The piston-pump G is of the well-known Worthington type ; built, 

 however, with especial attention to the requirements of the service 

 which is now being considered. H H shows the position of the in- 

 duction, and //of the eduction valves. _/ is the discharge- opening. 

 At K may be seen the steam or engine end of the machine, the 

 standard form used on all Worthington steam-pumps. The steam- 

 valve is an ordinary slide-valve, working upon a fiat surface over 

 ports or openings. The motion of this valve is produced by a 

 vibrating arm, L, which swings through thevvliole length of the 

 stroke with long and easy leverage. 



This valve motion is a prominent feature of the Worthington in- 

 dependent condenser. To it is due the complete exemption from 

 noise or concussive action. The two pumps are placed side by 

 side, and so combined as to act reciprocally upon the steam-valves 

 of each other. One piston acts to give steam to the other, after 

 which it finishes its own stroke and waits for its valve to be acted 

 upon before it can renew its motion. This pause allows all the 

 water-valves to seat quietly, and removes every thing like harsh- 

 ness of motion. 



As one or the other of the steam- valves must always be open, 

 there can be no dead point. The pump is therefore always ready 

 to start when steam is admitted, and is managed by the simple 

 opening and shutting of the throttle-valve. 



The operation of the condensing-apparatus is as follows : Steam 

 being admitted to the cylinders K, so as to set the pump in motion, 

 a vacuum is formed in the condenser, the engine-cylinder, the con- 

 necting exhaust-pipe, and the injection-pipe. This causes the in- 

 jection-water to enter through the injection- pipe attached at B, and 

 spray-pipe C, into the condenser-cone F. The main engine being 

 then started, the exhaust-steam enters through the exhaust-pipe at 

 A, and, coming into contact with the cold water, is rapidly con- 

 densed. The velocity of the steam is communicated to the water, 

 and the whole passes through the cone /" into the pump ff at a 

 high velocity, carrying with it, in a thoroughly commingled condi- 

 tion, all the air or uncondensable vapor which enters the condenser 

 with the steam. The mingled air and water are discharged by the 

 pump through the valves and pipe at /, before sufficient time or 

 space has been allowed for separation to occur. 



'It will be seen that the zone in which the condensation takes 

 place is small, and the rapid effect is due only to the immense sur- 

 face exposed by the spraying water. In case the water accumu- 

 lates in the condenser-cone F, either by reason of an increased 

 supply or by a sluggishness or even stoppage of the pump, as soon 

 as the level of the water reaches the spray-pipe and the spray be- 

 comes submerged, the vast surface is reduced to a minimum, only 

 a small annular ring being exposed to the steam from the main en- 

 gine. The vacuum is immediately broken, and the exhaust-steam 

 escapes by blowing through the injection-pipe and through the 

 valves of the pump, and out the discharge-pipe at _/, forcing the 

 water ahead of it : consequently flooding does not occur. 



These condensers have been constructed from those of a very 

 small size up to those of enormous power. Two, which are 

 probably the largest independent condensers in the world, are now 

 applied to an engine of 8,000 horse-power, the injection-water of 

 which amounts to 15,000 gallons a minute, or what is equivalent to 

 about 20,000,000 gallons a day. Many of them are in use in con- 

 nection with stationary steam-engines, and with marine engines on 

 boats running in fresh water. The Worthington condenser is also 

 used in connection with surface condensers on sea-going steamers, 

 where it has a field of usefulness that is at once apparent to those 

 who will but consider its functions. It performs the duty of two 

 distinct pumps, — the air-pump and the circulating pump. \\ 



