SOME years ago, in the merry scramble to get home quickly from one of the America cup races of Sandy Hook, the steamer Monmouth found herself overlapping the yacht Corsair as these two speedy craft were nearing a turning buoy in the old Gedney Channel. The writer, who was aboard the Monmouth noting that the two vessels, in the wish to make a close turn at the buoy, were drawing yery closely together, was watching the action of the bow wave and wash and wake of the one vessel upon the other. When the onmouth had drawn half her length ahead of the Corsair the latter sheered slightly toward the Monmouth apparently with the intention of swinging in closely under her stern, preparatory to turning. After the Corsair bow had approached slowly to within a certain distance of the Monmouth the yacht suddently closed in and struck the Monmouth The blow was delivered as swiftly as though the helm had been put hard over for the purpose. I t was evident to the writer that the lateral force which swung the Corsair's bow so quickly against the Monmouth J was due to the lateral infow of the water, displaced at the bow of the "Monmouth as it closed upon her stern. Naval Constructor D. W. Taylor recently investigated this matter in the course of some interesting experiments in the model tank at \ashington, in which he determined the action of yessels upon one another when they are steaming in close proximity and t,upon parallel courses. This investigation proved lhat under such circumstances any two ships have a strong tendency to close in upon one another. Judging from the cabled reports, the ramming of the “Olympic” was due to conditions similar to those above referred to. The cruiser “Hawke,” a rclatively insignifcant vessel of 7,000 tons displacement, was steaming abreast of and in rather close proximity to the “Olympic,” when the cruiser's navigating officer decided apparently to pass under the stern of the big ship. He probably put his helm oyer to what would have been the correct amount to enable him to execute this maneuver safely in undisturbed water; but as soon as his bow swung over into the wash of the steamer the “Hawke” appears to have been drawn again!t the “Olympic,” exactly as was the “Corsair” against the “Monmouth." The disaster serves to show that there is safetv in size. The ship which did the ramming weighs about 7,000 tons; the “Olympic” at the time of the disaster weighed probably about 60,000 tons. Judging from the speed of the “Hawke,” she struck a blow which probably would have sent a ship of ayerage size to the bottom; but so huge is the “Olympic” that the enormous rent which was torn in her skin-plating and the fooding.which followed seem to have had but little efect upon her stability. She was never at any time in serious danger. The extra strength and stifness of her bulkheads rendered them amply sufcient to withstand the strain of fooded compartments. It is probable that if the accident had happened at sea and in rough weather the big ship would have made her way comfortably hack to port. The Radium Engine I N his remarkable British Association address, Sir William Ramsay stated that th e disintegration of radium liberated three and one-half million times the energy available by the explosion of an equal yolume of detonating gas-a mixture of one volume of oxygen with two volumes of hydrogen. He pointed out that the major part of this energy comes apparently from the expulsion of particles (that is, of atoms of helium) with enormous velocity. “Suppose,” says Sir William, “suppose that the cnergy in a ton of radium could be utilized in thirty years instead of being evolved at its invariable slow rate of one thousand seyen hundred and sixty years for one-half disintegration, it would sufce to propel a ship of 15,000 tons, with engines of 15,000 horse-power, at the rate of 15 knots an hour, for thirty years, practically the lifetime of the ship. To do this actually requires one and one-half million tons of coaL" Here is a statement of radium's possibilities that may well give a steam engineer pause. Why bother about thermo-dynamics, about Carnot cycles, about the relative merits of turbines and reciprocating engines? \hy not develop the radium engine and conserve our coal supplies, and manipulate ounces of radium instead of tons of coal? At one fell blow all our elaborate coal-cony eying machinery disappears, and with it roaring furnaces, the blackened faces of stokers, and all the sooty paraphernalia that the word “steam engine” stands for. The possibilities are far more romantic on paper than in actual fact. In the frst place, where are we to get a ton of radium? Sir William himself in times past has placed the total supply of radium in the world, in laboratories, at much less than a pound. Physicists and chemists have time and time again pointed out the enormous personal risk involved in handling eyen a half grain of comparatively pure radium. Bacteria, insects and even mice, we believe, have actually been killed by radium rays, suitably applied, to be sure. What will be the efect upon a man sitting in a room containing, let us say, ten pounds of radium? “ould he ever emerge alive? Obviously, the mere difculty of handling so terrible a substance imposes problems far more diffcult of solution than those which the old steam engine cver offered. Assuming that we really had a safe method of handling a large quantity of radium, how arc we to make its energy available in practical form? Some totally new type of prime mover must be deYeloped, some contrivance which will render it possible for electrons hurled into space with the speed of light to do their work. Then again there is the subject of materials to be considered. Radio-actiye substances are no respecters of ordinary containers. The particles pre-jected from radium permeate most substances with comparative ease. To confne them would be a far more serious task than the insulation of a steam pipe. Stupendous as the problem is, who shall be b:Jld enough to say that it will never be solved? After all, is the utilization of the enormous energy contained in a half grain of radium any more startling than the transformation of the energy pent up in [ shovelful of black coal? I f the radium engine ever does come, it will simply be another instance of the triumph of mind oyer matter. From the Complex to the Simple AnARKED step was taken in the simplifcation of prime movers when Watt's cumbersome bfam engine, with its ingenious but elaborate parallel motion, gave way to the present standard reciprocating type, with only piston rod, cross head and connecting rod interposed between piston and crank. An even greater advance toward ideal simplicity occurred when, after years of efort by inventors to produce I practical rotary, Parsons brought out his compact, though costly, turbine, in which the energy of the steam is developed on a zigzag path through multitudinous rows of fxed and moving blades. And now comes lr. Tesla with a motor which bids fair to carry the steam engine another long step toward the ideally simple prime mover-a motor in which the. fxed and revolving blades of the turbine give place to a set of steel disks of simple and cheap construction. If the flow of steam in spiral curves between the adjoining faces of fat disks is an efcient method of deyeloping the energy of the steam, the prime mover would certainly appear to haye been at last reduced to its simplest terms. The further development of the unique turbine which we describe elsewhere will be followed with close attention by the technical world. The results attained with this small high-pressure unit are certainly fattering, and give reason to believe that the addition of a low pressure turbine and a condenser would make this type of turbine as highly efcient as it is simple and cheap in construction and maintenance. Lessons of the Transcontinental Flight ON September 12th and 13th two biplanes, a Wright, piloted by Robert G. Fowler, and a Curtiss, driven by J ames Ward, ldt San Francisco and New York, respectiyely, in an attempt to fy across the continent in less than thirty days. Under the rules the fight must be fnished by October 10th. In view of the automobile record of ffteen days, the fyers thought they had ample time, even allowing for accidents. Special trains with severa. extra machines were reported to be in close pursuit, and if any accidents were met with, it was expected that repairs would be promptly made. Aviator Fowler made an excellent start on September 12th, circling over the Golden Gate and San Francisco Bay and making his frst stop at Sacramento. After replenishing, he continued on to Colfax in the foot-hills of the Sierras. He was just beginning the long climb of more than 5,000 feet to the summit (7,018 feet) when, at Alta, the control wire of the yertical rudder broke and he came futtering down in spirals. The machine was badly broken, but Fowler fortunately was not seriously injurcd. A delay of ten days occurred before the biplane was ready to fy again. The start of Ward from Governor's Island on the 13th seems to have resulted in the bad luck generally attributed to that number. Little Ward is the youngest and lightest aviator of the transcontinental race trio. After losing his way at the start, he was delayed by motor troubles of various kinds. chiefy by lack of lubrication, due to faulty operation of the oil pump or leakage of oil from thc crank case. EYen after testing his new motor thoroughly on terra frma, he was unable to fly many miles before he was forced to alight for further repairs. In alighting he hit a tree and smashed his machine again, which caused hjm to abandon the race. An excellent start was made by Calbraith P. Hogers on Sunday, September 17th. Rogers, who like his brother, Lieut. Rogers of the N ayy, fies a Wright biplane, departed from Sheepshead Bay at 1,:33 P. M. on Sunday. He few directly across Brooklyn ard New York, crossed the Hudson opposite Madison Square, and picked out the Erie tracks by means of white streamers that had been placed on the ground along the line of the railroad. He few without a stop to :iddletown, N. Y., where he arrived 1'y'i hours after his start from Sheepshcad Bay. The total distance covered was 84 miles, which corresponds to an average speed of 48 miles an hour. In starting from the race track at Middle-town the next morning, Rogers came to grief and smashed his machine. The place from which to start was very restricted and the machine was un-- able to lift the heavy six-foot-four aviator quickly enough to avoid a large willow tree directly in his path. Rogers skillfully turned aside and cleared the tree, only to hit the top of another tree, which upset his machine and tumbled it to the ground. Rogers landed upon his feet after a fall of 30 feet or more and was uninjured, but his aeroplane was badly smashed. In four days, however, he had secured new parts and reconstructed his machine, and on September 21st, at 2:29 P. M., he left Middletown. \ith a strong, favorable wind to aid him, he covered 80 miles or more in 1 hour and 6 minutes, and alighted at Hancock at 3:35 P. M. The next day he covered 250 miles in all, but got of his course at Susquehanna and made a detour to Scran-ton, Pa., before reaching Binghamton. He was over G hours in fight and fnally reached Elmira. The results of the race to date haye demonstrated that training in cross-country fying is essential in order to make a good performance in a race of this kind. Rogers' accident was due to faulty judgment, but besides this he wandered from the course owing to his inexperience in cross-country work. The accident which happencd to Fowler is onc which should not happen to any well-made aeroplane. This is not the only time that a control wire has broken on a \right machine while in fight. The delay caused by the breakage of his rudder wire may cost Fowler the race. He is indeed lucky that he escaped without serious injury, as the vertical rudder is considered by the Wrights to be quite essential to their system of control. Using the warping alone Fowler managed to descend in spirals, but he was unablE to pick a suitable landing place.