284,505. White, A. E., (Sperry Development Co.). April 21, 1927. Recording by co-ordinates; particular operations.-An apparatus for recording various characteristics of a railway track under normal operating conditions comprises a gyroscopic means for maintaining a fixed base line and mechanism for recording on a chart driven by a car moving over the track (1) the track elevation and inclination of car body to axle thereof, (2) the rail curvature, (3) the gauge, and (4) the shocks due to passage over rail joints. The chart 10, Fig. 4, is unwound from a supply roll 11 on to a receiving roll 12<1> by passing over a feeding roll 12 rotated at a speed proportional to that of the car by gearing 26 and an adjustable cone belt drive 23 operatively connected to one or more synchronous motors 21 controlled by an electric transmitter 14 driven by sprocket gearing from an axle 16 of the car. Track elevation recorder. To the trucks on opposite sides of the car is connected a pair of cables 35, 36, Fig. 1, passing up through guide tubes 37, 38 around pulleys 39, 40 to opposite ends of a beam 41 pivoted centrally in a spring- supported journal 42. The beam 41 has secured thereto one end of a rod 43, the other end being carried in a swivel bearing on a bracket 45. The rod 43 is provided with an arm 46 connected by an adjustable link 47 to a lever 48 mounted on a pivot 49 carried by an arm 56 of a gyroscope, Fig. 2, comprising a rotor spinning about a vertical axis 51 in a vertical ring 52 pivotally mounted .on a horizontal ring 53 pivoted in fixed brackets 54, the journal shaft 55 thereof carrying the arm 56. Follow-up devices may be provided to cause the pivot 49 to follow the movements of the gyroscope. The lever 48 carries at its lower end a pen arm 61 with a pen 62, which records with respect to a base line 62<1> the difference in rail elevation. To record the tilt of the carbody with respect to its axle the pivot 49 is provided with an extension carrying a pen arm 60 maintained parallel to the side of the car-body by a parallel linkage 88, the pen 63 co-operating with a base line 63<1>. The pen arms 60, 61 may be formed as sleeves in which the pens are adjustably mounted, as by rack and pinion connections. Rail curvature and movements of car trunk in response thereto. A gyroscope 70, Fig. 9, having a horizontal spinning axis in a vertical ring 71 carried by a follow-up element 72 will turn relatively to the car at a curve, and will cause the follow-up element 72 to energize a two-way motor 80 to cause the element 72 to follow the gyroscope and drive an electric transmitter 85, which through a cable 86 actuates a cam mechanism such as a cam-roller 90 to control the movements of a pen arm 91. The transmitter 85 is provided with a handle 87, so that the pen may be set in any desired initial position. Zone pens for indicating in which quadrant the record is being made may be provided, these pens operating as described in Specification 195,633. The behaviour of the car truck to curves is recorded by a pen 109 connected to a spring-controlled cable 108 attached to the upper end of a rod 106 detachably connected to a shaft 101, having a forked arm 100 engaging a pin 102 on the car truck, said arm being aligned with the swivelling centre of the truck. Gauge recorder. To record the distance between the rails, a pair of arms 20, Figs. 10, 12, provided with hardened steel shoes to engage the inside flange of the rails are pivoted to links 122 connected to the car truck, and are connected at their upper ends to cables 126, 127 passing over pulleys 128, 129 to a bar 130 pivoted on one end off a spring-controlled rack bar 131. Movement of the rack due to variation in the gauge actuates a transmitter 140, which is electrically connected to cam mechanism controlling a recarding pen 135. To render the gauge recorder inactive each link 122 has secured thereto a link 141 carried by. a spring-controlled beam 142, connected at its mid-point to the piston of a cylinder 147 controlled by fluid under pressure. Cams 150<1> on the shoes co-operate with fixed stops 143 on the trucks to guide them into operative position. To retard the outward movement of the shoes after a predetermined degree of movement an escapement device as shown in Fig. 11 is employed. The rack 131 actuates a pinion 150 on the transmitter shaft, which shaft carries a ratchet wheel 151 engaging a pawl 152 on a gear 153, the pawl being guided and constrained by a spring 158 towards the end 159 of a slot 160. The gear 153 remains inactive to drive the escapement wheel 155 until the rawl 152 is moved to the other end of the slot by movement of the rack, thereafter the escapement retards further outward movement. Shock recorder for rail' joints. The car truck supports a cylinder 160, Fig. 13, having a piston with a piston rod connected by a cross-head 165, member 166, and universal connection 168 to an arm 169 fixed to a bracket 170 on the journal box. The piston due to vibration is adapted to close one or more of a plurality of stepped contacts 171 to close a corresponding circuit or circuits through electromagnets 180<1> - - - 185<1> to actuate the respective pens 180 - - 185, Fig. 15. As shown in Figs. 15, 16, the pens are arranged in staggered relation an opposite sides of a common-ink trough 186 and produce a record as at A, B, Fig. 15. The circuits of the contacts may include other electromagnets to actuate corresponding counting mechanisms to register values proportional to the magnitude of the faults. Gyroscopic apparatus. The gyroscope may be centralized and locked by pressing inwardly a cone 70<1>, Fig. 9, adapted to engage the end of the gyro shaft. Another arrangement for setting the axis in any desired position comprises a pair of bails 200, 201 pivoted on a bracket carried by the gyroscope ring 71, Fig. 18, and geared together by segments 204, 205. When the ends of the bails are drawn together they engage a lug on the casing to swing it about its axis in the ring 71. This movement is effected through an arm 207 and link 208 connected to one end of a lever 209, Fig. 19, pivoted upon the ring 71 and controlled by a spring 210, the other end of the lever being provided with a pin 216 engaging a forked plunger 215, the arms 217 of which extend through substantially semi-circular holes 218 in the base plate 73. The arms 217 carry a corrugated ring 220 to facilitate non-slipping engagement with the pin 216, rotation of the plunger 215 by knob 221 effecting the desired setting in azimuth.