40 ANNUAL OF SCIENTIFIC DISCOVERY. 



"I would sugirest to superintendents of railroads row in ojierntion, the 

 trial of a few rods in length of superstructure with string-piecv-;, and two sets 

 of cross-ties. First place in the ballast-ties six by eight inches, two and a 

 half feet apart from centre to centre; upon these place longitudinal sills, also 

 six by eight inches; lastly, upon the latter place the smaller cross-ties sup- 

 porting the rail, about three by six inches, and two or two and a half feet 

 apart from centre to centre; the bottom of the longitudinals being about an 

 inch above the ballast. The bottom of the string-piece is supposed to be 

 elevated about an inch above the ballast. It appears to me that the elasticity 

 insured to the rail, throughout its entire length, by the arrangement, will be 

 found to diminish, to a very great extent, the destructivepor/y action which 

 the engines exert upon the rails of all the superstructures now in use. Experi- 

 ence would soon point out the proper dimensions, and distances apart, of the 

 timbers to be employed for engines of any given weight, in order to insure 

 the requisite degree of elasticity, which evidently admits of being varied to 

 any extent which may be found desirable. The increased quantity of timber 

 involved in this proposed plan, is an evident objection to it; but experience 

 only can indicate whether the attendant advantages which it possesses may 

 not more than counterbalance this objection, together with any others to 

 which it may be liable. Besides the greater presumed durability of the rail, 

 from the fact that no portion of it rests on a rigid support, we should secure a 

 much more efficient rail-joint, inasmuch as the joints would rest upon the 

 npper cross-ties, instead of between the ties, as in the present preferred prac- 

 tice; thus combining increased strength of joint with greater uniformity of 

 elasticity. We also should elevate the rail more beyond the influence of 

 snow. Moreover, should this expedient enable us to obtain that certain (un- 

 certain?) amount of elasticity of rail which all engineers concede to be so 

 important a desideratum, it will doubtless lead to the adoption of more effi- 

 cient supports for the lower cross-ties themselves, supports which may extend 

 below the influence of rain and frost, and thus effect a very important reduc- 

 tion of expense for rectification of the track, besides dispensing with the use 

 of ballast. The greatest objection in the employment of such supports, 

 hitherto, has been the increased rigidity of track attendant on them, and by 

 which the destruction of the rail is greatly accelerated. But if we can devise 

 a means of modifying or entirely annulling this rigidity in the rail by a pro- 

 cess entirely independent of the foundation on which the rail rests, then this 

 objection vanishes; and the way seems to open for arriving at a much more 

 perfect superstructure than has hitherto been used. 



" I hope that the subject may be regarded by some of our intelligent super- 

 intendents as being of sufficient interest to induce them to make a trial of it, 

 if only for a few lengths of rail." 



GARDINER'S COMPOUND CAR WHEEL AND AXLE. 



The invention consists of a compound axle of three parts, and a compound 

 wheel of six parts. The journal part of the axle is about sixteen inches 

 long, of sufficient length for the bearing, and passes to the centre of the hub 

 of the wheel; the other part is of sufficient length to reach from centre to 

 center of the hubs, constituting the main or middle part of the axle. It is 

 joined to each end by the short axles, and so coupled together inside of the 

 hub as to render it as strong as the solid axle. The wheel is pressed on the 

 short axle in the ordinary way, giving the result of a loose and tight wheel 



