March 34, 1882.] 



KNOWLEDGE 



447 



and doubtless with advantage, but wo were considering 

 their use in tlie above calculation. More could certainly 

 not be added, without bringing the oar to a position in 

 which a large part of the oarsman's strength would be 

 wasted in pushing the water from the boat instead of 

 parallel to the boat's leugtli. 



It is, then, a simple matter of demonstration that the 

 stroke must be changed, in the modern racing craft, in 

 respect of the time during which the oar is in the water. 

 If a greater rapidity of propulsion is required, as we have 

 proved, and neither the number of strokes per minute, nor 

 the length of the stroke, can be increased beyond a certain 

 point, which does not suffice to give the necessary rapidity 

 of propulsion, it follows of necessity that the oar must be 

 a shorter time in the water and a longer time out of the 

 water. 



This is commonly misunderstood, especially by persons 

 who have never rowed in light racing craft. They say, 

 the stroke must be kept " long in the \\ ater," and in one 

 use they are perfectly right : the stroke of the oar in the 

 ater must be as long as possible in distance, but not in 

 'nil''. But then "comes answer like an Absey book," You 

 inhocate a quick stroke, and more than so many — say from 

 torty to forty-four strokes per minute — should not be taken. 

 This again is true, the oar must be dashed through the 

 water quickly (or rather, for in good rowing there is very little 

 slip, must be dashed down sharply against the water and the 

 1 loat lifted along by sharp strong pressure against the water), 

 '•ut not too often to the minute. But then, again, comes 

 ill the objection. That means a slow feather, for if each 

 ! jke from feather to feather occupies a certain time, 

 ^iii)rtening the stroke means lengthening the feather ; and 

 every moment that the oar is out of the water the boat is 

 losing speed. Again we replj', the objection is valid ; but 

 it is a necessity of the case that to give the swift, sharp 

 impulse to the long, but quickly drawn, stroke, the oarsman 

 must take a longer time in the feather. Of course, the best 

 thing of all would be to have as many strokes as possible 

 pir minute, the longest possible stroke, taken in the 

 shortest possible time, with the longest possible oars, 

 and in the lightest possible boats. But the rowers 

 IjL-ing limited in their powers, the choice must be 

 made between long dragging strokes with lightning 

 feather, and long but swift strokes with less rapid 

 recovery ; and as the long dragging strokes would simply 

 not propel a boat at all at the swift pace of a modern 

 racing craft, the long, swift stroke must he taken. (Here 

 Pendragon, of the iuy'er<?f, who sat heavily upon the Editor, 

 three years ago, for asserting the necessity of these long, 

 but swiftly taken strokes, may come in if he please, and 

 say we advocate short, swift strokes, which every great 

 race of the last ten years has shown to be ineffec- 

 tive.) 



To sum up, — a modem racing eight, whatever may have 

 ■ n the tub practice of the crew, must be driven by 

 ilge-hammer strokes, long and sweeping, but sharply 

 t '.ken, and resulting from the concentrated exertion of all 

 tho energies of the body, followed by a moderately quick 

 I ' ' overy, during which the oarsman gathers himself 

 ' ^'ether as it were for the next great effort, a momentary 

 ! luse (which in old times would have been called a hang 

 on the feather, and deservedly criticised as a defect) 

 preceding the simultaneous plunge of the eight oars to 

 grip the beginning of the stroke. In other words, a stroke 

 must be taken which, with the old fashioned boats, even 

 when they had attained their best speed, would have 

 meant breaking the oars, if the men were only strong 

 enough to give it. How this impulsive stroke is to be 

 given we shall consider in our next. 



THE CRYSTAL PALACE ELECTRICAL 

 EXHIBITION. 



Sevexth Notice. 



THE Lane-Fox (Fig. 3) difters somew hat from the two 

 lamps described last week, the chief difference being 

 m the connection between the filament and the wires from 

 the generating machine. The glass bulb is about 3 in. 

 ong and 2^ in. in diameter. The filament is made from 

 bass-broom, and is connected to short pieces of platinum 

 wire, which are fused into the glass tul>es A, B. The 

 lower ends of the wires are immersed in small quantities of 



mercury, M, M'. Two copper wres, C, C, pass from the 

 mercury through the lower portions of the tubes. A, B, 

 (which merge into one tube at D), and thence outside the 

 lamp. The wires are then soldered to the portions of the 

 socket connected to the machine. The tubes. A, B, and 

 their continuation, D, are filled ^vith plaster of Paris, P, 

 and wool, W, keeping the copper wires and mercury in 

 position. 



The Maxim lamp (Fig. 4) exhibits another fonn of 

 contact or connection. The globe is about '2^ inches in 

 diameter, the neck. A, B, being turned inwards until the 

 aperture at C, is reduced from about an inch to a quarter 

 of an inch. A glass rod, CD, is then fused on at C, and 

 has two platinum wires passing through it. Externally the 

 wires are continued to E and F (outside the neck), so that 

 in fitting the lamp into its socket, the wires come into 

 contact with two insulated springs, each of which is con- 

 nected to one of the machine wires. Inside the lamp, the 

 platinum wires are flattened and bent into a kind of hook 

 (H). The filament, which is fiat and in the shape of a 

 gridiron, or letter il (for Maxim), is made from paper, so 

 that in cutting it out, there is little or no difficulty in 

 making the extremities considerably broader than the other 



