| Description | Date | Identifier | |
| Speedometer calibration for the 40/50 HP chassis, considering different wheel sizes and customer complaints. | 12th Jan 1934 | Box 165 \ 4 img234 | |
| Request to modify the dials of Bentley Revolution Indicators to show a red triangular space. | 18th Jan 1934 | Box 165 \ 4 img235 | |
| Return of a Smith Electrical Rev Indicator to the manufacturer for replacement. | 19th Jan 1934 | Box 165 \ 4 img236 | |
| Letter to S. Smith & Sons Ltd. returning an electrical rev counter due to large temperature variations and requesting a new model for testing. | 19th Jan 1934 | Box 165 \ 4 img237 | |
| Letter from S. Smith & Sons regarding the return of a sample Electrical Rev Indicator and the promise of a new one. | 22th Jan 1934 | Box 165 \ 4 img238 | |
| Internal request to order a combined speedometer and instrument patch for an Essex Terraplane car. | 30th Jan 1934 | Box 165 \ 4 img239 | |
| Cancellation of a speedometer order for a Terraplane if it needs to be imported from the U.S.A. | 7th Feb 1934 | Box 165 \ 4 img240 | |
| Correspondence regarding a sample rev-counter dial for Bentley Revolution Indicators sent for inspection. | 9th Feb 1934 | Box 165 \ 4 img241 | |
| The introduction of a new sample dial for Bentley Revolution Indicators. | 12th Feb 1934 | Box 165 \ 4 img242 | |
| Alteration and production of a revolution indicator dial for the Bentley chassis. | 12th Feb 1934 | Box 165 \ 4 img243 | |
| Letter from Hasler Telegraph Works discussing the testing and adjustment of Hasler Revolution Indicators. | 27th Apr 1934 | Box 165 \ 4 img244 | |
| Page 2 of a letter from Hasler Telegraph Works regarding a possible error in revolutions per minute during frequency adjustment. | 20th Aug 1934 | Box 165 \ 4 img245 | |
| The overhaul of a unique, special lightened type Bentley combined revolution indicator and clock. | 29th May 1934 | Box 165 \ 4 img246 | |
| The modification and calibration of a Bentley Revolution Indicator. | 6th Jun 1934 | Box 165 \ 4 img247 | |
| Letter from Kollsman Instrument Co. regarding the redesign and pricing of a type 70-05 tachometer. | 13th Jun 1934 | Box 165 \ 4 img248 | |
| Request to obtain a speedometer test rig with a 2:1 reduction gear from Jaeger Instruments Ltd. | 7th Sep 1934 | Box 165 \ 4 img249 | |
| Request to process payment for an invoice received from S. Smith & Sons for a Revolution Indicator. | 15th Oct 1934 | Box 165 \ 4 img250 | |
| Oil leak on the Bentley speedometer drive, referencing a similar issue on a 20/25 model. | 17th Oct 1934 | Box 165 \ 4 img251 | |
| Clarifying that a revolution indicator from Messrs. Smiths belongs to the Plant Department. | 18th Oct 1934 | Box 165 \ 4 img252 | |
| Speedometer change for a Streamlined Bentley due to a new gear ratio. | 5th Nov 1934 | Box 165 \ 4 img253 | |
| Revised specifications for the Spectre's servo and speedometer drive. | 9th Nov 1934 | Box 165 \ 4 img254 | |
| Request to determine the wheel revolutions per mile for a 'Spectre' chassis with specific tyres for speedometer calibration. | 19th Nov 1934 | Box 165 \ 4 img255 | |
| Letter to A.T. Speedometer Co. Ltd. regarding progress on a new speedometer and magnetic interference testing on another model. | 2nd Jan 1935 | Box 165 \ 4 img256 | |
| Letter from a speedometer supplier regarding magnetic interference tests and a request to borrow an instrument. | 8th Jan 1935 | Box 165 \ 4 img257 | |
| Request to fit a new type Bentley speedometer and rev counter to vehicle reference 5.B.IV. | 9th Jan 1935 | Box 165 \ 4 img258 | |
| Letter responding to an enquiry about a Graham Paige speedometer, explaining why one cannot be loaned. | 15th Jan 1935 | Box 165 \ 4 img259 | |
| Letter from S. Smith & Sons regarding a Graham Paige speedometer and damping issues in sample instruments. | 16th Jan 1935 | Box 165 \ 4 img260 | |
| Speedometer calibration data for a standard 20/25 chassis with 11/50 axle and 19' tyres. | 29th Jan 1935 | Box 165 \ 4 img261 | |
| Letter from A.T. Speedometer Co. regarding modifications to returned instruments and upcoming samples. | 29th Jan 1935 | Box 165 \ 4 img262 | |
| Continuation letter from A. T. Speedometer Co., Ltd. regarding a three-month timeframe. | 29th Jan 1935 | Box 165 \ 4 img263 | |
| Return of Bentley A.T. instruments for conversion to an up-to-date specification. | 4th Feb 1935 | Box 165 \ 4 img264 | |
| Expressing concern over delays in developing legible speedometers for R-R and Bentley cars. | 8th Feb 1935 | Box 165 \ 4 img265 | |
| Proposed improvements to vehicle instruments for Spectre, R-R, and Bentley models. | 8th Feb 1935 | Box 165 \ 4 img266 | |
| Customer complaints about unreadable mileage figures and the need for immediate improvements. | 8th Feb 1935 | Box 165 \ 4 img267 | |
| Stock and order status of speedometers for R.R and Bentley Chassis. | 11th Feb 1935 | Box 165 \ 4 img268 | |
| The return of two A.T. speedometers for modification. | 13th Feb 1935 | Box 165 \ 4 img269 | |
| Speedometer improvements and supply issues from Smiths for various car models. | 13th Feb 1935 | Box 165 \ 4 img270 | |
| Proposed modifications for an A.T. Speedometer. | 14th Feb 1935 | Box 165 \ 4 img271 | |
| Correspondence regarding speedometers for R-R and Bentley cars. | 15th Feb 1935 | Box 165 \ 4 img272 | |
| Letter to S. Smith & Sons regarding speedometer improvements, specifically requesting larger trip figures for Rolls-Royce and Bentley models. | 14th Feb 1935 | Box 165 \ 4 img273 | |
| The concluding page of a letter from the Sales Manager regarding the introduction of larger trip figures. | 16th Feb 1935 | Box 165 \ 4 img274 | |
| Letter to A.T. Speedometer Co. Ltd. regarding the modification of lightweight speedometers and rev-counters. | 16th Feb 1935 | Box 165 \ 4 img275 | |
| Letter from the A.T. Speedometer Co. Ltd. discussing modifications to instrument dials, drives, and magnets. | 18th Feb 1935 | Box 165 \ 4 img276 | |
| Letter from The A.T. Speedometer Co. confirming a telephone conversation and enclosing a copy of another letter. | 18th Feb 1935 | Box 165 \ 4 img277 | |
| Standardization of larger trip figures on speedometers for R-R and Bentley chassis. | 18th Feb 1935 | Box 165 \ 4 img278 | |
| Correspondence concerning proposals for speedometers with larger trip figures for chassis. | 20th Feb 1935 | Box 165 \ 4 img279 | |
| Speedometer case sizes, larger trip figures, and concave lighting for R-R and Bentley chassis. | 21th Feb 1935 | Box 165 \ 4 img280 | |
| Timelines for introduction and concave lighting for instrument panels. | 21th Feb 1935 | Box 165 \ 4 img281 | |
| Speedometers with larger trip figures for R-R and Bentley chassis, and associated delivery schedules. | 23th Feb 1935 | Box 165 \ 4 img282 | |
| Letter from S. Smith & Sons regarding a requested modification to speedometers for larger trip figures. | 22th Feb 1935 | Box 165 \ 4 img283 | |
| Letter to S. Smith & Sons regarding the cost implications of a new shrouded magnet speedometer design. | 23th Feb 1935 | Box 165 \ 4 img284 | |
| The design and supply of speedometers with larger trip figures and concave lighting for RR and Bentley chassis. | 22th Feb 1935 | Box 165 \ 4 img285 | |
| Order for two rev counters reading up to 5000 R.P.M. | 25th Feb 1935 | Box 165 \ 4 img286 | |
| The introduction of new speedometers with larger trip figures and concave lighting for various car models. | 28th Feb 1935 | Box 165 \ 4 img287 | |
| Timing and cost for introducing an improvement to the Bentley model, including a shrouded magnet design. | 26th Sep 1935 | Box 165 \ 4 img288 | |
| Design and layout of instruments with concave dials, including a new speedometer. | 27th Feb 1935 | Box 165 \ 4 img289 | |
| Introduction of new speedometers with larger trip figures and concave lighting for RR and Bentley cars. | 27th Feb 1935 | Box 165 \ 4 img290 | |
| Order for a 'Spectre' speedometer cable. | 28th Feb 1935 | Box 165 \ 4 img291 | |
| Speedometers for R-R and Bentley Chassis with larger trip figures. | 6th Mar 1935 | Box 165 \ 4 img292 | |
| Letter from a supplier explaining a delay in quoting for speedometers due to material sourcing issues. | 5th Mar 1935 | Box 165 \ 4 img293 | |
| Letter to S. Smith & Sons regarding a supply issue with new magnet steel for speedometers. | 6th Mar 1935 | Box 165 \ 4 img294 | |
| Visit from S. Smith & Sons to discuss introducing new speedometers with concave dials and larger trip figures. | 7th Mar 1935 | Box 165 \ 4 img295 | |
| Chassis testing schedules and specifications for instrument panels. | 7th Mar 1935 | Box 165 \ 4 img296 | |
| Developing larger trip and distance mileage figures for speedometers, noting a competitor has already implemented them. | 7th Mar 1935 | Box 165 \ 4 img297 | |
| Introduction of modified speedometers for R-R and Bentley cars. | 8th Mar 1935 | Box 165 \ 4 img298 | |
| Requesting a reversion to the standard attachment method for speedometer and rev counter drive flex. | 18th Mar 1935 | Box 165 \ 4 img299 | |
| Complaint about poor speedometer lighting and a request for a correct thermometer due to a new axle fitment. | 24th Apr 1935 | Box 165 \ 4 img300 | |
| Request to alter the speedometer calibration and improve instrument panel illumination for chassis B-10-DG. | 25th Apr 1935 | Box 165 \ 4 img301 | |
| Letter to A.T. Speedometer Co. Ltd. requesting a form of adjustment for new speedometers. | 1st May 1935 | Box 165 \ 4 img302 | |
| Request to place an order for a 54' long speedometer flexible drive. | 2nd May 1935 | Box 165 \ 4 img303 | |
| Letter from the A.T. Speedometer Co., Ltd. regarding two methods for varying the calibration of new instruments. | 3rd May 1935 | Box 165 \ 4 img304 | |
| Standardisation of an A.T. Speedometer with larger figures on mileage disc and shrouded magnet. | 1st Mar 1935 | Box 165 \ 4 img305 | |
| Cost estimate for introducing extra jigs and tools for the 'U' series chassis, including a breakdown of costs and an approval log. | 19th Mar 1935 | Box 165 \ 4 img306 | |
| Standardisation of an A.T. Speedometer with larger figures on mileage discs and shrouded magnets. | 1st May 1935 | Box 165 \ 4 img307 | |
| Cost estimation for extra jigs, tools and equipment for the 'JW' series chassis, including a cost comparison between old and new parts. | 19th Mar 1935 | Box 165 \ 4 img308 | |
| Standardisation of an A.T. speedometer with larger figures, designed to improve legibility and reduce weight. | 1st May 1935 | Box 165 \ 4 img309 | |
| Cost analysis for the standardisation of a spur gear part for the Bentley 'E' series 10Let chassis. | 26th Mar 1935 | Box 165 \ 4 img310 | |
| Proposal from Smiths to use a single 100 M.P.H. speedometer dial for the 20/25 model. | 15th May 1935 | Box 165 \ 4 img311 | |
| Letter of complaint to A.T. Speedometer Co. Ltd. regarding noisy speedometer flexible drives. | 17th May 1935 | Box 165 \ 4 img312 | |
| Letter from a supplier investigating complaints about noisy speedometer flexible drives. | 21th May 1935 | Box 165 \ 4 img313 | |
| Letter from A. T. Speedometer Co. Ltd. regarding the lubricant for flexible drives. | 21th May 1935 | Box 165 \ 4 img314 | |
| Cause of noisy speedometer flexes, suggesting that prolonged storage hardens the grease. | 22th May 1935 | Box 165 \ 4 img315 | |
| Extract from a letter regarding lubricant solidification in flexible speedometer cables due to long storage. | 21th May 1935 | Box 165 \ 4 img316 | |
| Rejecting a suggestion to change the speedometer dials for the 20/25 model due to legibility concerns. | 27th May 1935 | Box 165 \ 4 img317 | |
| Letter to A.T. Speedometer Co. Ltd. confirming the decision on speedometer dials for the 20/25 and 40/50 models. | 28th May 1935 | Box 165 \ 4 img318 | |
| Letter from The A.T. Speedometer Co., Ltd. confirming speedometer dial specifications for the 20/25 and 40/50 models. | 31th May 1935 | Box 165 \ 4 img319 | |
| Requesting an additional Hasler rev counter for the Experimental Electrical Laboratory. | 24th Jun 1935 | Box 165 \ 4 img320 | |
| Internal order request for a Hasler Revolution Speeds Indicator for the Electrical Experimental Department. | 1st Jul 1935 | Box 165 \ 4 img321 | |
| Notice about new type speedometers for Bentley and 20/25 chassis, advising against self-repair. | 12th Jul 1935 | Box 165 \ 4 img322 | |
| Potential purchase of a Zeiss Ikon Motor Indicator and comparing it with similar British-made instruments. | 27th Aug 1935 | Box 165 \ 4 img323 | |
| Requesting the return of a faulty Electrical Laboratory Rev Counter due to a sticking needle. | 30th Aug 1935 | Box 165 \ 4 img324 | |
| Repairs to Hasler Counter No. 30136, quoting a report on its condition and instructing staff not to interfere with instruments awaiting repair. | 1st Sep 1935 | Box 165 \ 4 img325 | |
| Urgent request to A.T. Speedometer Co. Ltd. for an experimental speedometer for a Bentley chassis. | 21th Sep 1935 | Box 165 \ 4 img326 | |
| Letter confirming the order and dispatch of one instrument with 759 revs for a Bentley chassis. | 24th Sep 1935 | Box 165 \ 4 img327 | |
| Request to send an order to the A.T. Speedometer Co. for a Bentley Speedometer. | 2nd Oct 1935 | Box 165 \ 4 img328 | |
| Request to rewind the solenoid coil for a single cylinder test bed's electrically operated rev-counter. | 4th Oct 1935 | Box 165 \ 4 img329 | |
| Letter to Mr. E.A. Watson of Joseph Lucas Ltd. arranging a meeting in Birmingham. | 23th Oct 1935 | Box 165 \ 4 img330 | |
| Request to locally procure 24 Detonindex neon tubes for ignition pencil indicators. | 24th Oct 1935 | Box 165 \ 4 img331 | |
| Letter to S. Smith & Sons Ltd. inquiring about the development of electrical rev counters for their chassis. | 12th Nov 1935 | Box 165 \ 4 img332 | |
| Letter from S. Smith & Sons regarding experiments on a new electrical Rev. Indicator and sample availability. | 13th Nov 1935 | Box 165 \ 4 img333 | |
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