Fig. 1. 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. [September, 



Fig. 4. 



Fisf. 2. 



require a degree of pressure to attain the requisite adhesion, which 

 invariably superinduces a most injurious friction in the bearings. 

 With the view of obviating this defect of the plan of communicating 

 motion by friction surfaces, Mr. Galloway submits the following 

 contrivance of his own : — 



"In this arrangement, shown at Fig. 4, it is proposed to use two engines 

 of the form of which stationary engines are usually constructed, that is to 

 say, they would have their beams above the cylinders and cranks : d d are the 

 cranks, which are at a right angle to each other; c c the intermediate shaft; 

 i a i is a double coned wheel connected by the cyhndric part a. this is all 

 cast in one piece, and accurately turned on the conical parts b b ; e g and./ h 

 are two wheels attached to axes i and ;. They are conical at the parts /and 

 e, and cvlindrical at the parts g and h. The diameters are one-fourth of the 

 large cones b b. The axis i is the screw axis, and ./ the adjusting axis ; k is 

 a spring which, by means of screws, can be made to force the cone/ towards 

 the axis c c. If, therefore, we suppose a given force to be thus communi- 

 cated it will advance the surfaces of the cones together with four times the 

 pressure there is exerted at i. In this condition of the parts, if the engmes 

 be put in motion thev will cause the cones b b to turn the smaller wheels 

 eg fh, in opposite directions ; but the pressure necessary to produce contact 

 will be principally exerted between the cylinders ff and h, which, being a 

 rolling motion, is free from friction, and the power of the engine wdl thus 

 be transmitted to the screw with only a loss of power entailed by the small 

 amount of friction at t. It is obvious also in this contrivance that there is 

 scarcely any friction at the bearings of i andj, which, owing to the cones 

 having the force communicated at two opposite points in their periphery, 

 exert no pressure on their bearings, except that of gravity." 



FiR. 3. 



We question whether this expedient, though a very good one, is 

 the one wanted. A rotatory engine appears to be the desideratum, in 

 those cases in which the screw requires to be driven at a great speed; 

 and in other cases it is the best plan, we think, to employ engines of a 

 short stroke, and couple them immediately to the shaft from which 

 the screw derives its motion. This has been done in Mr. Wimshurst s 

 vessel with verv good effect, and, we believe, will invariably be found 

 the best mode where the screw is employed merely as an auxiliary, 

 or occasional impelling power. We find by a note, that Mr. Wim- 

 shurst's vessel, in which this plan is adopted, had not been constructed 

 until after Mr. Galloway's book was written; to which circumstance 

 we must attribute the omission of all notification respecting her. We 

 therefore feel it right to say, as Mr. Galloway would, we have no 

 doubt, have said, liad the opportunity been afforded him, that Mr. 

 Wimshurst's plan of driving the screw is the least exceptionable of 

 any we have met with. 



London as it is. By Thomas Shotter Boys. Folio. 1842. 



Mr. Boys' " London as it is" is by no means London as it ought to 

 be, or ought to be shown. It has, in truth, altogether disappointed us 

 fo in no one respect is it at all satisfactory, the subjects being, with 

 merely one or two exceptions, very badly selected, either quite stale, 

 or otherwise of little interest, and very poorly represented, at least as 

 views of buildings, for the architecture is very slovenly, loosely, and 

 incorrectly drawn, and treated as altogether of subordinate interest m 

 comparison with the figures. As far as buildings are '^""^"■f • X' ^ 

 as eood or even better representations, and those, oo, far less sta e in 

 noFnt of subiect, are to be met with in some of the penny and two- 

 ^"nv perXals. There are, no doubt, many who wiU prefer Mr 

 Boys' bustling London street- scenes, with crowds of vehicles of every 

 description. To far abler executed architectural subjects; but we 

 ques on whether any of that class of persons are the purchasers of 

 four-guinra books, unless they be those whom Sir Robert Peel terms 



*''TheUu"of''"Londonasitis'' would naturally lead us to suppose 

 that the work is intended to exhibit more especially the recent archi- 

 tecture and improved parts of the metropolis, by way of contrast to 

 London as it was about thirty years ago Yet if -f ..^^^ ''J ^f ^^^^ 

 purpose, he has adopted a most singular mode of following out such 

 5lan, th«e being comparatively few subjects which might not have 

 £een shown sixty years ago. Such bui dings as Ten pie bar St. 

 James's Palace, and the Tower-or rather its mere outs de walls- 

 have itte to ecommend them for selection; and the views are so 



mited as to number, that they ought to have been carefully chon 

 nor do they possess novelty of any kind, having been ^ep eseite I 

 before, over^nd over again, and in '"''".vnstances very much beUer. 

 Nay, as if it was so exceedingly interesting and ^ea'^tiful a sub ec 

 Una it could not be too much studied, Mr. Boys has given too d ifte ent 

 V ;ws of Temple Bar; while of Newgate-wh.ch has so much of 



