| Description | Date | Identifier | |
| The failure of a 2nd Motion Shaft in a gear box, detailing mileage, suspected cause, and the implemented solution. | 27th Jun 1939 | Box 136 \ 2 scan0125 | |
| Photograph of a helical gear layshaft cluster. | 3rd Jul 1939 | Box 136 \ 2 scan0126 | |
| Drawing for the arrangement of Timken Bearings for a gearbox layshaft intended for dynamometer testing. | 3rd Jul 1939 | Box 136 \ 2 scan0127 | |
| Letter from Overdrive Gears Ltd. regarding an improved overdrive design and potential collaboration. | 18th Jul 1939 | Box 136 \ 2 scan0128 | |
| Confirmation to dispense with the servo on the small gearbox for the Junior Rationalised range. | 20th Jul 1939 | Box 136 \ 2 scan0129 | |
| Design and scaling of a 'Junior Gearbox' to achieve weight savings for smaller cars. | 28th Jul 1939 | Box 136 \ 2 scan0130 | |
| Comparison table of component metrics, possibly weights or costs, for different engine sizes. | 28th Jul 1939 | Box 136 \ 2 scan0131 | |
| Design specifications for the Junior gearbox and axle, considering engine sizes and sales projections. | 5th Aug 1939 | Box 136 \ 2 scan0132 | |
| Parts list and request for blueprints for a Gear Box Gear Test Rig. | 12th Aug 1939 | Box 136 \ 2 scan0133 | |
| Typed list of parts with their corresponding part numbers and quantities required. | 24th Apr 1939 | Box 136 \ 2 scan0134 | |
| Inquiring about the Alvis gearbox patent, referencing the Hillman Minx, for potential use in the Myth Gear-box. | 9th Oct 1939 | Box 136 \ 2 scan0135 | |
| Acquisition of an Alvis gearbox patent specification, thought to be common with Minx cars. | 11th Oct 1939 | Box 136 \ 2 scan0136 | |
| Letter to Ransome & Marles Bearing Co. Ltd. inquiring about the status of bearing preload tests, now required for the Aero Department. | 11th Oct 1939 | Box 136 \ 2 scan0137 | |
| Gear change lever design for the American market, comparing column-mounted shifters to floor-mounted ones. | 21th Oct 1939 | Box 136 \ 2 scan0138 | |
| Order for a Hillman 14 gearbox from Pickford's. | 23th Oct 1939 | Box 136 \ 2 scan0139 | |
| Alterations to the reverse mechanism of the Myth gearbox. | 3rd Nov 1939 | Box 136 \ 2 scan0140 | |
| Pencil sketch of a mechanical linkage for reverse operation. | 6th Nov 1939 | Box 136 \ 2 scan0141 | |
| Memo discussing difficulties with the reverse gear on the Myth and L.H. Phantom gearboxes and proposing a solution. | 6th Nov 1939 | Box 136 \ 2 scan0142 | |
| Hand-drawn sketch with dimensions for a proposed reverse operation on a Left Hand Phantom. | 6th Nov 1939 | Box 136 \ 2 scan0143 | |
| Experiments with a synchro-mesh gearbox and reverse selector spring modifications. | 14th Nov 1939 | Box 136 \ 2 scan0144 | |
| Proposal from an Italian inventor for an automatic change speed gear system. | 29th Nov 1939 | Box 136 \ 2 scan0145 | |
| Letter from Eligio Mirone listing the advantages of an automatic change speed gear. | 12th Dec 1939 | Box 136 \ 2 scan0146 | |
| Secret memo discussing proposals for the simplification of the Senior Rationalised Gearbox. | 12th Dec 1939 | Box 136 \ 2 scan0147 | |
| Secret memorandum discussing the simplification of the Senior Rationalised Gearbox and a proposal to reverse gear positions. | 12th Dec 1939 | Box 136 \ 2 scan0148 | |
| Sending an engine unit to the repair department for overhaul to be used in a Vulture gearbox test rig. | 20th Dec 1939 | Box 136 \ 2 scan0149 | |
| Request for the manufacture of parts for a simplified synchromesh scheme for a rationalised gearbox. | 28th Dec 1939 | Box 136 \ 2 scan0150 | |
| Request to issue a covering order to Messrs. S. Smith & Sons Ltd. for a Right Angle gearbox. | 28th Dec 1939 | Box 136 \ 2 scan0151 | |
| Requesting information and feedback on the Cotal gearbox and discussing seaplane landing gear. | 19th Jan 1940 | Box 136 \ 2 scan0152 | |
| Typed letter to O. Bowden regarding the trial of a car with a Cotal gearbox and arranging a follow-up visit. | 19th Jan 1940 | Box 136 \ 2 scan0153 | |
| Letter from Morris Motors Ltd. acknowledging correspondence and informing that the proposed meeting date is not convenient. | 23th Jan 1940 | Box 136 \ 2 scan0154 | |
| List of new blueprints and drawings for the PL. 65 Revised Senior Gearbox. | 25th Jan 1940 | Box 136 \ 2 scan0155 | |
| Letter from Morris Motors regarding an opportunity to view a Cotal gearbox at Wolseley Motors. | 25th Jan 1940 | Box 136 \ 2 scan0156 | |
| Accompanying blueprints for a Revised Senior Gearbox. | 25th Jan 1940 | Box 136 \ 2 scan0157 | |
| Letter from Wolseley Motors Limited regarding an interest in the Cotal gearbox. | 26th Jan 1940 | Box 136 \ 2 scan0158 | |
| Drawings for a revised senior gearbox and a request to produce 7 sets. | 26th Jan 1940 | Box 136 \ 2 scan0159 | |
| Letter to O. Boden of Morris Motors Ltd. regarding co-operation. | 27th Jan 1940 | Box 136 \ 2 scan0160 | |
| Letter to W.M.J. Thomas of Wolseley Motors Ltd. regarding the arrangement of a meeting. | 27th Jan 1940 | Box 136 \ 2 scan0161 | |
| Letter from the Managing Director of Wolseley Motors Ltd. to Mr. Robotham arranging a visit. | 30th Jan 1940 | Box 136 \ 2 scan0162 | |
| Modifications to the ride control for Right Hand Cars with Senior Gearboxes. | 31th Jan 1940 | Box 136 \ 2 scan0163 | |
| Letter to W. Thomas of Wolseley Motors Limited postponing a visit due to snow. | 1st Feb 1940 | Box 136 \ 2 scan0164 | |
| Production methods for gear tooth serrations on an RG.181 insert outer cone. | 7th Feb 1940 | Box 136 \ 2 scan0165 | |
| Invitation from Wolseley Motors Ltd to view and test Cotal gearbox components and activities. | 9th Feb 1940 | Box 136 \ 2 scan0166 | |
| Manufacturing method for an outer cone insert's internal teeth. | 9th Feb 1940 | Box 136 \ 2 scan0167 | |
| Missing prints for a Senior Gear Box 3rd Speed Driven Gear, urging action to allow machining to proceed. | 12th Feb 1940 | Box 136 \ 2 scan0168 | |
| Alteration note for a Senior Gearbox Reverse Shaft, adding centre drilling at each end. | 13th Feb 1940 | Box 136 \ 2 scan0169 | |
| Letter to W.M.W. Thomas of Wolseley Motors arranging a meeting. | 12th Feb 1940 | Box 136 \ 2 scan0170 | |
| Dispatch of 2 blueprints for the ER.5332 2nd speed driven gear. | 15th Feb 1940 | Box 136 \ 2 scan0171 | |
| Blueprints for a revised senior gearbox driven gear. | 15th Feb 1940 | Box 136 \ 2 scan0172 | |
| Visit to Wolseley's to inspect a Cotal gearbox and compare it with a standard model. | 16th Feb 1940 | Box 136 \ 2 scan0173 | |
| Development of a gearbox, including issues with magnets and plans for a new design based on a Chrysler unit. | 16th Feb 1940 | Box 136 \ 2 scan0174 | |
| Updates and part replacements for the Senior Range gearbox and actuating gear. | 16th Feb 1940 | Box 136 \ 2 scan0175 | |
| Changes and updates to a gearbox design, including features to be removed and modifications to its components. | 18th Feb 1940 | Box 136 \ 2 scan0176 | |
| Letter to Wolseley Motors Ltd. arranging a factory visit and the collection of a loaned Cotal gear box. | 16th Feb 1940 | Box 136 \ 2 scan0177 | |
| Letter to Morris Motors regarding the loan of a Cotal gearbox, gearbox research, and injection equipment. | 16th Feb 1940 | Box 136 \ 2 scan0178 | |
| Letter of inquiry to 'Autocar' magazine regarding a pre-selector synchromesh gearbox. | 16th Feb 1940 | Box 136 \ 2 scan0179 | |
| Letter from Wolseley Motors Ltd regarding arrangements for the collection of a Cotal Gearbox. | 17th Feb 1940 | Box 136 \ 2 scan0180 | |
| Letter to Wolseley Motors Ltd. arranging a visit and requesting information on a patented two-speed marine gearbox. | 20th Feb 1940 | Box 136 \ 2 scan0181 | |
| Letter from Morris Motors Ltd. regarding the Cotal gearbox and petrol injection equipment. | 20th Feb 1940 | Box 136 \ 2 scan0182 | |
| Letter from Iliffe & Sons Ltd. discussing a pre-selector gearbox mechanism and its designer. | 21th Feb 1940 | Box 136 \ 2 scan0183 | |
| Letter from Wolseley Motors Ltd confirming they are gathering information on the Cotal gearbox. | 22th Feb 1940 | Box 136 \ 2 scan0184 | |
| Alternative methods for securing outer cones in the Senior Gearbox due to issues with peening after cyanide hardening. | 22th Feb 1940 | Box 136 \ 2 scan0185 | |
| Questioning the use of bearings for the side shaft of the Junior Rationalised Gear Box. | 22th Feb 1940 | Box 136 \ 2 scan0186 | |
| Inquiry about a pre-selector operation described in an 'Autocar' article, requesting a demonstration or drawings. | 24th Feb 1940 | Box 136 \ 2 scan0187 | |
| Trial to rely on the press fit of the cones alone for the Senior Gear Box. | 24th Feb 1940 | Box 136 \ 2 scan0188 | |
| Letter from Wolseley Motors Ltd to W.A. Robotham regarding Cotal gearbox drawings and a proposed visit. | 24th Feb 1940 | Box 136 \ 2 scan0189 | |
| Continuation page of a letter from the Managing Director of Wolseley Motors Ltd. | 26th Feb 1940 | Box 136 \ 2 scan0190 | |
| Letter to W.M.W. Thomas of Wolseley Motors Ltd. about rescheduling a meeting. | 26th Feb 1940 | Box 136 \ 2 scan0191 | |
| Requesting a layout to assess the impact of fitting a Cotal gearbox, including a marine unit, into a Bentley. | 27th Feb 1940 | Box 136 \ 2 scan0192 | |
| Confirming the dispatch of preliminary blueprints for a gearbox casing. | 27th Feb 1940 | Box 136 \ 2 scan0193 | |
| Letter from A.B. Oliver responding to an enquiry about a gearbox, stating a demonstrator is unavailable and proposing a meeting. | 27th Feb 1940 | Box 136 \ 2 scan0194 | |
| Letter to A.B. Oliver, Esq. arranging a factory visit. | 1st Mar 1940 | Box 136 \ 2 scan0195 | |
| Revised clutch actuation for the Senior Gearbox (R.H. side change). | 1st Mar 1940 | Box 136 \ 2 scan0196 | |
| Blueprints for a revised clutch casing to suit a single lever actuation. | 1st Mar 1940 | Box 136 \ 2 scan0197 | |
| Blueprints and modifications for a Senior Gearbox with a right-hand side change. | 1st Mar 1940 | Box 136 \ 2 scan0198 | |
| Concluding page of a set of instructions, marked as page 2. | 1st Mar 1940 | Box 136 \ 2 scan0199 | |
| Revisions to the Senior Gearbox, including the speedo drive, damper pump casing, and dispatch of associated blueprints. | 1st Mar 1940 | Box 136 \ 2 scan0200 | |
| Left-hand side change modification for the Senior Gearbox, including associated part drawings. | 1st Mar 1940 | Box 136 \ 2 scan0201 | |
| Modifications and blueprints for the Senior Gearbox's Servo Drive to accommodate Tecalemit chassis lubrication. | 1st Mar 1940 | Box 136 \ 2 scan0202 | |
| Letter from A.C. Oliver to Mr. Robotham arranging a meeting to present the 'Oliver' gearbox. | 2nd Mar 1940 | Box 136 \ 2 scan0203 | |
| Gathering recommendations for a Cotal gearbox to cope with the 5 1/2 litre engine. | 4th Mar 1940 | Box 136 \ 2 scan0204 | |
| Translated document detailing the performance and usage of the Cotal electro-magnetic gearbox. | 20th Feb 1940 | Box 136 \ 2 scan0205 | |
| The price, performance, and power-absorption of Cotal gearboxes, with comparisons to Peugeot. | 4th Mar 1940 | Box 136 \ 2 scan0206 | |
| The recommended size of a Cotal gearbox for a 5.5-litre engine and plans for destructive testing. | 4th Mar 1940 | Box 136 \ 2 scan0207 | |
| List of gearbox-related parts, drawings and patent specifications loaned by Mr. Oliver. | 5th Mar 1940 | Box 136 \ 2 scan0208 | |
| Diagrams showing multiple sectional views of a pre-selective synchro-mesh gearbox. | 5th Oct 1938 | Box 136 \ 2 scan0209 | |
| Technical drawing showing multiple cross-sections of a pre-selective synchro-mesh gearbox. | 5th Oct 1938 | Box 136 \ 2 scan0210 | |
| Blueprints and parts for modifications to the gearbox and servo drive on Senior Range Cars. | 7th Mar 1940 | Box 136 \ 2 scan0211 | |
| Letter from Hallam, Sleigh & Cheston confirming arrangements for two heaters. | 7th Mar 1940 | Box 136 \ 2 scan0212 | |
| Notice detailing outstanding sections of instructions for the Senior Range Gear Box. | 8th Mar 1940 | Box 136 \ 2 scan0213 | |
| Gear and axle ratios for the Rippletto and Myth Class cars. | 8th Mar 1940 | Box 136 \ 2 scan0214 | |
| Comparison table of performance specifications for various non-Rolls Royce cars from the 1930s. | 8th Mar 1940 | Box 136 \ 2 scan0215 | |
| Comparative data table of various car models and their performance specifications. | 8th Mar 1940 | Box 136 \ 2 scan0216 | |
| Comparison table of specifications for various motor cars from 1937-1938. | 8th Mar 1940 | Box 136 \ 2 scan0217 | |
| Comparison table of vehicle specifications for various car models. | 8th Mar 1940 | Box 136 \ 2 scan0218 | |
| Comparison table of specifications for a Humber Saloon 'Snipe' and a Bentley Coupe Drop Head. | 8th Mar 1940 | Box 136 \ 2 scan0219 | |
| Technical particulars and specifications for the Minx Gearbox, detailing teeth counts and dimensions. | 8th Mar 1940 | Box 136 \ 2 scan0220 | |
| Grinding operation for splines and the possibility of cutting grooves in steel cores for gear teeth. | 8th Mar 1940 | Box 136 \ 2 scan0221 | |
| Gear and axle ratios for the Junior Gearbox on the Rippletto and Myth class cars. | 8th Mar 1940 | Box 136 \ 2 scan0222 | |
| Technical data sheet comparing specifications of various competitor cars from the 1930s. | 8th Mar 1940 | Box 136 \ 2 scan0223 | |
| Comparative data table of specifications for various British cars from the 1930s and 1940. | 8th Mar 1940 | Box 136 \ 2 scan0224 | |
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