METHOD OF SECURING CARRIAGE WHEELS. 189 



VII. 



Method to prevent the Accidents which frequently happen 

 from the Linchpins of Carriages breaking or coming out: 

 by Mr. J, Vajity, of Liverpool, Coachmaker*. 



SIR, 



J[jL EREWITH you will receive a model of an axle-tree Contrivance t» 

 for public machines, intended to prevent the wheel from 5ents"rom th» 

 coming off, if the linchpin should break, and thereby pre- linchpin of a 

 vent many dangerous consequences. When the idea first w ^ eM ° reak " 

 suggested itself to me, I put it in practice in a stage coach, out. 

 which has since run from Liverpool to Litchfield, a distance 

 of eig'ity-lour miles, six days per week, for the last six 

 inontns. During that time several instances have occurred 

 ID which the linchpins have broke or come out, but owing 

 to this contrivance no accident has happened therefrom. 

 We almost daiiy hear of stage coaches being upset, which 

 more frequently arises from linchpins breaking than from 

 any other cause. 



In offering this model to the Society of Arts &c. for their 

 inspection, I anticipate the pleasure of their sanction, as I - 

 can furnish satisfactory vouchers of its proved utility. 

 I am, Sir, 



Yours, respectfully, 



J. VARTY. 



• 



Description of Mr. Vartfs Linchpin* 



Mr. Varty's, contrivance is shown in fig. 4, and 5, Plate pescribei. 

 VI. Fig. 4 is a section of the nave of a carriage wheel, 

 with the axle-tree A A in it; and fig. 5 is a separate view 

 of the axletree. a, fig. 5, is the linchpin detached; it is 

 put through an oblong hole in the axle as usual, but there 

 is likewise an additional linchpin b, to make it complete, 

 which is fixed in a recess cut foi it in the axle, and turns 

 pn a pin (as is shown in the figure) into the hole left by re- 



* Trans, of the Society of Arts, vol. XXVII. p. 145. For this 

 icreutiou the silver medal was voted to Mr. Varty. 



moving 



