210 



THE CIVIL ENGIN'EER AND ARCHITECTS JOURNAL. 



[July, 



than riidinary nvthtic forte, and shows himself capable of adhering 

 faithfully to tho irenuiue spirit of the style he adopts — be it Gothic 

 or any other — without tlie slightest taint of servile imitation. 

 Tills is high praise, but in his case not excessive, because amply 

 merited; and we only regret that we cannot extend it to many 

 other things which, lieing of greater magnitude, and affording 

 much greater scope for design, ouglit accordingly to have mani- 

 fested talent proportioned to the occasion. 



For aught wc know to the contrary, many of tlie designs here 

 exhibited have been selected from among a number of others sent 

 in at competitions for the respective buildings; and if such be 

 really the case, we are bound to suppose — at least, until there be 

 proof to the contrary, that they were in each instance, the best 

 offered; yet few of them show particular talent. In fact, there is 

 a striking sameness both as to quality and ideas in subjects belong- 

 ing to the same class, which causes them to appear "made to order" 

 in compliance with some one of the prevailing fashions of the 

 day, among which Tudor and Elizabethan come in for an ample 

 share of favour. Of such style. No. 1037, "New Schools, &c., re- 

 cently built in the district of Christ Church, St. George-in-the- 

 East," G. Smith, shovvs a good application. There is also some- 

 thing good in No. 104!), "Design for an Elizabethan Villa," C. W. 

 C. Edmonds; for which, however, "mansion" would have been a 

 more a])proi)riate designation than "villa." Indeed, we almost 

 wonder that the latter term is not altogether repudiated as fopjiish 

 and outlandish, by the admirers of our "good Old English" tastes 

 and fashions. 



In any other style than mediaeval and Old English there are 

 scarcely any designs at all, except "The Assize Courts at Liver- 

 pool," which drawing we spoke ot last month; and No. 1108, "The 

 Great Hall of the Euston Station," P. C. Hardwicke, a cleverly 

 executed interior, and not devoid of considerable scenic effect; yet, 

 at the same time marked by oversights and defects in its design 

 that might easily have been corrected or avoided. In our opinion, 

 the ceiling is too much decorated, — so much so as to cause the 

 lower part of the apartment to appear bare and unfinished, while 

 the large carved brackets or trusses which support it are out of 

 keeping with the order below, and take off considerably from its 

 importance, more especially as the columns themselves are shorter 

 than they needed or ought to have been; for strange to say, the 

 pedestals on which they are raised are made higher than the 

 railing between them, which produces a very awkward and dis- 

 agreeable effect. No. lOSl ought to-have shown ns at least a hand- 

 some specimen of modern design, it being according to the cata- 

 logue for a Building for the Vernon Gallery, but for w hich informa- 

 tion we should neier ha\e suspected that it was intended for a 

 picture gallery at all. "We will here bring our remarks to a close, — 

 somewhat abruptly, perhaps, but as it happens, time does not per- 

 mit us to say more. 



ON THE PADDLES OF STEAMERS. 



On the Paddles of Steamers — their Figure, Dip, Thickness, Mate- 

 rial, Number, &jC. By Thomas Ewbank, Esq., City of New York. 

 [From the Journal of the Franklin Institute.'] 



The world is awakening to the propulsion of steam- vessels, and 

 nations are about to compete with each other in increasing their 

 speed. Steamboat racing is too congenial with the age to be re- 

 ))ressed ; its sjiirit, so far from having been laid by legal exorcisms, 

 or confined, as heretofore, to lake and river craft, has now seized 

 the ocean for its theatre, and laughs outright at adjurations. En- 

 gineers and naval constructors, animated with the ambition of 

 Olympian com])etitors, are preparing for a series of Atlantic cha- 

 riot races, compared with which, the whole Naumachian spectacles 

 of old were despicable puerilities. 



Impressed with the interest of a contest unexampled in the 

 annals of mechanical science, and one so characteristic of the pro- 

 gi-ess of civilization, the following experiments were undertaken 

 with a view of eliciting facts that seemed imperfectly known. 

 Speculations on ])ropelling abound. 1 am not aware that a series 

 of exjjerfments similar to these, limited and imperfect as they are, 

 has been prosecuted. If any such are recorded, I have not met 

 with theOi. 



Experiments on variowsly formed Paddles, made on the Harlem River, 



New York, in 1845 and 1848. 



For this purpose, the boat, fig. 1, was employed. It was 12^ feet 



long, and 3^ feet across the middle. A wrought-iron shaft, 1 inch 



square, with a crank, extended across the gunwales, and turned in 



bearings bolted to tliem. Tlie ends of the shaft stretched 14. 

 inches over the sides of tlie boat. This prevented the wheels, 

 which were secured on their extremities, from throwing as much 

 water into the vessel as if they had been nearer ; and afforded a 

 better ojiportunity of observing the action of the blades. A person 

 seated at one cud of the boat readily turned the wheels, in either 

 direction, by alternately pushing from, and jjulling towards him, 

 two upright rods, which moved in joints at the bottom of the boat, 

 and were connected to the cranks by horizontal rods. 



The wheels were very light, and of the simplest construction. 

 One is shown at fig. 2. Eiglit slender arms of -j^ square iron, have 

 their inner ends cast in the central piece. 

 They extended 20 inches from the centre, 

 and thus made a 40-inch wheel. To stiffen 

 them, and transmit any strain upon one to 

 the whole, they were braced tightly together 

 by the wire o, o, o, which was wound round 

 each arm, and retained by slight notches at 

 the corners. The various blades or paddles 

 were cut out of stout sheet iron. S<iuare 

 sockets, to slide o*r the arms, were riveted 

 to them; by which means they were readily 

 adjusted and secured at uniform distances ' 



from the axes. All were of the same area — 49 inches. 



To test th6 qualities of the boat, and get her into working trim, 

 blades, 7 inches square (fig. 3), were fi.xed on the arms of both 

 wheels, and several excursions, u\> and down the 

 rivei', made with them. Their dip was 7 inches, or 

 rather more, for their upper edges were half an inch 

 below the surface. They were next remo\ed from 

 one wheel, and left on the other, as the standard liy 

 which to compare the effects of different shaped 

 ones. — They were distinguished as No. 1. Nearly 

 all the rest were formed from them: i.e. byre- 

 moving ])ortions from one part, and adding them to 

 other.s, as w ill be seen in the follow ing diagrams. 

 In this way there was no danger of making, through 

 mistake, one set of blades, of larger, or of less, superficial surface 

 than others, since no calculation of their areas was required. 



In all the figures, the paddles are supposed to sweep through 

 the water in the position they are represented in, the lowest sides 

 being those which descend lowest in the fluid. 



Fig. 4, — formed by cutting off the lower angles of fig. 3, and 

 ti-ansferring the pieces to the up|ier ones, 

 making a right-angled triangle, w itli sides 

 10 inches, and hypotenuse 14 inches. (By 

 mistake, the upper corners were cut away, 

 so as to leave the area of these blades 48 

 square inches, instead of 49.^ Eight of 

 these were fixed on the wheel (see b, fig. 1,) 

 to comjiete with the same number of fig. 3, 

 on a, both having 7i inches dip. 



It will be obvious that, as both sets were 

 attached to the same shaft, if one proved 

 more efficient than the other, the boat would 

 be turned from a straight course, and be inclined, more or less 

 abruptly, to the weaker or less efficient set. The result was, that 

 those marked fig. 3 overcame fig. 4; and though only in a smalj 

 degree, yet quite sufldcient to establish their superior effect on the 

 vessel's progress. As we were not always out of the influence of 



Fig. 3. 



Fig. i. 



