| Description | Date | Identifier | |
| Letter from S. Smith & Sons proposing various thermostat arrangements and referencing specific drawings. | 16th Sep 1937 | Box 156 \ 1 scan0256 | |
| Visit to Vauxhall Motors Ltd. to discuss the reliability of thermostats supplied by the British Thermostat Co. Ltd. | 17th Sep 1937 | Box 156 \ 1 scan0257 | |
| Vauxhall's thermostat testing methods and cooling system performance. | 17th Sep 1937 | Box 156 \ 1 scan0258 | |
| Summary of observations on competitor pump glands and thermostat units, with recommendations for development. | 17th Sep 1937 | Box 156 \ 1 scan0259 | |
| Diagram showing a modification to the thermostat top plate assembly to prevent leakage. | 17th Sep 1937 | Box 156 \ 1 scan0260 | |
| Letter to a supplier regarding failures of experimental thermostats and requesting design modifications on future orders. | 18th Sep 1937 | Box 156 \ 1 scan0261 | |
| Letter to S. Smith & Sons Ltd. regarding the standardisation of a thermostat unit. | 20th Sep 1937 | Box 156 \ 1 scan0262 | |
| Tests at Brooklands on a 6.B.1V car fitted with a Marston dummy shutter and thermostat for the M. series Bentley. | 20th Sep 1937 | Box 156 \ 1 scan0263 | |
| Results of a test on the 6.B.1V cooling system on the road and at Brooklands Track. | 20th Sep 1937 | Box 156 \ 1 scan0264 | |
| Summary report on the cooling system being standardised for the Bentley M. series. | 20th Sep 1937 | Box 156 \ 1 scan0265 | |
| Letter from The British Thermostat Co. Ltd. regarding an incorrect drawing and the dispatch of two valve stem top plate assemblies for examination. | 21th Sep 1937 | Box 156 \ 1 scan0266 | |
| Letter from S. Smith & Sons to C.S. Steadman arranging a meeting to discuss two separate matters. | 21th Sep 1937 | Box 156 \ 1 scan0267 | |
| Letter to S. Smith & Sons Ltd. arranging a meeting to discuss matters from a previous letter. | 24th Sep 1937 | Box 156 \ 1 scan0268 | |
| Letter from S. Smith & Sons confirming a meeting with Mr. C.S. Steadman. | 27th Sep 1937 | Box 156 \ 1 scan0269 | |
| Letter to The British Thermostat Co. Ltd. clarifying a dimension on a thermostat drawing. | 28th Sep 1937 | Box 156 \ 1 scan0270 | |
| Letter from The British Thermostat Co. Ltd. confirming a dimension on Drawing No. EB.3410 is correct. | 30th Sep 1937 | Box 156 \ 1 scan0271 | |
| Letter to Vauxhall Motors requesting information on their water pump gland design and experience with 'No-Co-Ro' corrosion inhibitor. | 30th Sep 1937 | Box 156 \ 1 scan0272 | |
| Letter from S. Smith & Sons regarding the testing of a drop-in type thermostat sent on a loan account. | 1st Oct 1937 | Box 156 \ 1 scan0273 | |
| Letter to a supplier regarding the failure of a thermostat during testing. | 5th Oct 1937 | Box 156 \ 1 scan0274 | |
| Page 2 of a letter regarding the return of defective parts. | 5th Oct 1937 | Box 156 \ 1 scan0275 | |
| Return of a failed thermostat to the British Thermostat Co. Ltd. | 5th Oct 1937 | Box 156 \ 1 scan0276 | |
| Letter to The British Thermostat Co. Ltd. requesting the repair and supply of two thermostats with specific operating temperatures. | 6th Oct 1937 | Box 156 \ 1 scan0277 | |
| Letter from The British Thermostat Co. Ltd. concerning a faulty thermostat where the valve head became loose due to a melted soldered joint. | 7th Oct 1937 | Box 156 \ 1 scan0278 | |
| Letter from The British Thermostat Co. Ltd. discussing a ball valve failure and thermostat testing. | 9th Oct 1937 | Box 156 \ 1 scan0279 | |
| Development of an improved and cheaper thermostat system for the B.III model. | 9th Oct 1937 | Box 156 \ 1 scan0280 | |
| Letter to The British Thermostat Co. Ltd. discussing soldering methods for a valve head. | 9th Oct 1937 | Box 156 \ 1 scan0281 | |
| Letter discussing experimental methods for thermostats, including soldering techniques and pressure testing. | 11th Oct 1937 | Box 156 \ 1 scan0282 | |
| Letter from S. Smith & Sons regarding Advice Notes for a P.V. type Thermostat. | 11th Oct 1937 | Box 156 \ 1 scan0283 | |
| Letter from The British Thermostat Co., Ltd. concerning the assembly and testing of a thermostat valve head. | 11th Oct 1937 | Box 156 \ 1 scan0284 | |
| Letter from The British Thermostat Co. Ltd. regarding a bellows unit pressure test. | 13th Oct 1937 | Box 156 \ 1 scan0285 | |
| Letter from The British Thermostat Co. Ltd. reporting on a thermostat pressure test. | 13th Oct 1937 | Box 156 \ 1 scan0286 | |
| Thermostat from S. Smith & Sons, Ltd. left for testing purposes on a loan account. | 14th Oct 1937 | Box 156 \ 1 scan0287 | |
| Instructing modifications to the cooling system of car 1.B.IV due to issues with the thermostat scheme. | 14th Oct 1937 | Box 156 \ 1 scan0288 | |
| The dispatch of a thermostat to central stores and its subsequent return. | 16th Oct 1937 | Box 156 \ 1 scan0289 | |
| Letter to The British Thermostat Co. Ltd. regarding a thermostat bellows failure and proposed solutions. | 16th Oct 1937 | Box 156 \ 1 scan0290 | |
| Following up on an outstanding invoice for Thermostat Assemblies and requesting payment authorization. | 16th Oct 1937 | Box 156 \ 1 scan0291 | |
| Letter from The British Thermostat Co., Ltd. confirming a meeting with Mr. Steadman. | 18th Oct 1937 | Box 156 \ 1 scan0292 | |
| Letter from Harrison Radiator Division regarding an outstanding invoice for thermostat assemblies. | 18th Oct 1937 | Box 156 \ 1 scan0293 | |
| Letter to The British Thermostat Co. Ltd. requesting modifications to two thermostats. | 20th Oct 1937 | Box 156 \ 1 scan0294 | |
| Letter from The British Thermostat Co. Ltd. regarding the modification, testing, and supply of two thermostat assemblies. | 21th Oct 1937 | Box 156 \ 1 scan0295 | |
| Letter from The British Thermostat Co. regarding the pressure testing and distortion of Vauxhall pattern thermostats. | 25th Oct 1937 | Box 156 \ 1 scan0296 | |
| Letter to The British Thermostat Co. Ltd. requesting a pressure test and investigation into thermostat design improvements. | 26th Oct 1937 | Box 156 \ 1 scan0297 | |
| Recalling a standardisation sheet for a Bentley radiator thermostat scheme due to failures and issuing a revised design. | 26th Oct 1937 | Box 156 \ 1 scan0298 | |
| Dispatch of two thermostats for examination and their subsequent return. | 27th Oct 1937 | Box 156 \ 1 scan0299 | |
| Letter to The British Thermostat Co. Ltd. discussing the testing of two thermostats and requesting modified units. | 27th Oct 1937 | Box 156 \ 1 scan0300 | |
| Letter requesting modified Vauxhall units with specific technical requirements. | 27th Oct 1937 | Box 156 \ 1 scan0301 | |
| Revised thermostat scheme for a Bentley radiator with dummy shutters. | 27th Oct 1937 | Box 156 \ 1 scan0302 | |
| Letter from The British Thermostat Co. Ltd. regarding the testing and supply of thermostat components. | 27th Oct 1937 | Box 156 \ 1 scan0303 | |
| Letter from The British Thermostat Co., Ltd. regarding thermostat testing, design modifications, and pricing. | 28th Oct 1937 | Box 156 \ 1 scan0304 | |
| Page 2 of a letter from The British Thermostat Co. Ltd. regarding thermostats and modifications. | 30th Oct 1937 | Box 156 \ 1 scan0305 | |
| Letter from The British Thermostat Co. asking for clarification on which Smith's unit part is being used for experiments on the Bentley. | 30th Oct 1937 | Box 156 \ 1 scan0306 | |
| List of parts and modifications for the Bentley 11 thermostat system and thermometer bottle. | 30th Oct 1937 | Box 156 \ 1 scan0307 | |
| Potential standardisation of the Bentley fixed shutter radiator. | 1st Nov 1937 | Box 156 \ 1 scan0308 | |
| Brief summary of four different thermostat schemes tested, detailing their advantages and disadvantages. | 1st Nov 1937 | Box 156 \ 1 scan0309 | |
| Summary comparing three different cost-saving schemes involving thermostat units and water pressure. | 2nd Nov 1937 | Box 156 \ 1 scan0310 | |
| Letter to The British Thermostat Co. Ltd. regarding the postponement of a thermostatic bypass system due to unsatisfactory running experience. | 2nd Nov 1937 | Box 156 \ 1 scan0311 | |
| Correspondence regarding a drop-in thermostat unit, requesting drawings and a list of supplied units. | 2nd Nov 1937 | Box 156 \ 1 scan0312 | |
| Invoice for a thermostat and a request for payment instructions. | 2nd Nov 1937 | Box 156 \ 1 scan0313 | |
| Letter concerning the postponement of thermostat standardisation and enclosing a new drawing for an interchangeable unit. | 3rd Nov 1937 | Box 156 \ 1 scan0314 | |
| Advice note detailing the cost of thermostats related to drawing BGA.2073. | 4th Nov 1937 | Box 156 \ 1 scan0315 | |
| Letter to The British Thermostat Co. Ltd. requesting a quotation for small diameter bellows. | 4th Nov 1937 | Box 156 \ 1 scan0316 | |
| Order for three thermostats from The British Thermostat Co. Ltd. | 4th Nov 1937 | Box 156 \ 1 scan0317 | |
| Letter requesting a price estimate for a 'drop in' type thermostat from The British Thermostat Co. Ltd. | 11th Nov 1937 | Box 156 \ 1 scan0318 | |
| Letter to S.Smith & Sons Ltd. regarding a 'Drop In' type thermostat, requesting its opening temperature and a quotation for 200 units. | 11th Nov 1937 | Box 156 \ 1 scan0319 | |
| Quotation from The British Thermostat Co. Ltd. for 200 Drop-in Type Thermostats. | 12th Nov 1937 | Box 156 \ 1 scan0320 | |
| Quotation from S. Smith & Sons for Smiths Bellows type Thermostats. | 12th Nov 1937 | Box 156 \ 1 scan0321 | |
| Confirming the decision to adopt a complete thermostat unit from an external supplier. | 13th Nov 1937 | Box 156 \ 1 scan0322 | |
| Returning an incorrect thermostat for a replacement from Messrs. S. Smith & Sons. | 15th Nov 1937 | Box 156 \ 1 scan0323 | |
| Letter to Messrs. S. Smith & Sons Ltd regarding a quotation and the return of a unit. | 15th Nov 1937 | Box 156 \ 1 scan0324 | |
| Letter from S. Smith & Sons (Motor Accessories) Ltd confirming the despatch of a B.V. Thermostat for testing. | 16th Nov 1937 | Box 156 \ 1 scan0325 | |
| Arrangement of the thermostat, piping, and other connections for the Bentley 111. | 17th Nov 1937 | Box 156 \ 1 scan0326 | |
| Letter to Dennis Bros. Ltd. requesting information on thermostat operational issues due to cooling water deposits. | 23th Nov 1937 | Box 156 \ 1 scan0327 | |
| Costs of various aluminium castings for different vehicle parts. | 23th Nov 1937 | Box 156 \ 1 scan0328 | |
| Cost comparison for iron castings between outside suppliers and in-house foundry. | 23th Nov 1937 | Box 156 \ 1 scan0329 | |
| Thermostat assembly failure during endurance testing due to the bellows rubbing on the aluminium casting. | 25th Nov 1937 | Box 156 \ 1 scan0330 | |
| Sketch showing the cause of thermostat failure due to the casing's actual contour fouling the bellows. | 23th Nov 1937 | Box 156 \ 1 scan0331 | |
| Letter from Dennis Bros Ltd discussing issues with thermostat bellows caused by hard water and proposing an alternative design. | 25th Nov 1937 | Box 156 \ 1 scan0332 | |
| Letter from Dennis Brothers Limited discussing the service life and performance of thermostat bellows. | 27th Nov 1937 | Box 156 \ 1 scan0333 | |
| Letter from Dennis Brothers Ltd. regarding sending a corrected blueprint for a thermostat arrangement. | 27th Nov 1937 | Box 156 \ 1 scan0334 | |
| Letter to a supplier regarding the production and supply of a thermostat unit for a Bentley. | 29th Nov 1937 | Box 156 \ 1 scan0335 | |
| Inquiry to AC-Sphinx Sparking Plug Co. Ltd. regarding the potential supply of Harrison thermostats. | 30th Nov 1937 | Box 156 \ 1 scan0336 | |
| Letter from AC-Sphinx Sparking Plug Co. Ltd. regarding the potential manufacturing of the Harrison thermostat. | 1st Dec 1937 | Box 156 \ 1 scan0337 | |
| Letter to The British Thermostat Co. Ltd. discussing methods for fixing an internal tube to a bellows plate. | 3rd Dec 1937 | Box 156 \ 1 scan0338 | |
| Letter regarding the manufacturing process for a tube and bellows plate, advising a delay on drawing alterations. | 6th Dec 1937 | Box 156 \ 1 scan0339 | |
| Instructions for setting and checking the thermostat unit for the 'M' Series Bentley. | 8th Dec 1937 | Box 156 \ 1 scan0340 | |
| Instructions for the assembly, testing, and supply of thermostat units and associated components. | 3rd Dec 1937 | Box 156 \ 1 scan0341 | |
| Letter requesting quotations for three different types of thermostat units from The British Thermostat Co. Ltd. | 8th Dec 1937 | Box 156 \ 1 scan0342 | |
| Request for a quotation for thermostat units. | 8th Dec 1937 | Box 156 \ 1 scan0343 | |
| Letter to S. Smith & Sons, Ltd. regarding an American thermostat being sent for inspection. | 14th Dec 1937 | Box 156 \ 1 scan0344 | |
| Instructing the dispatch of a thermostat made by Harrison Radiator Corporation to Messrs. Smiths for examination. | 14th Dec 1937 | Box 156 \ 1 scan0345 | |
| Quotation from The British Thermostat Co. Ltd. for various types of thermostats. | 14th Dec 1937 | Box 156 \ 1 scan0346 | |
| Quotation for thermostats from The British Thermostat Co., Ltd. | 14th Dec 1937 | Box 156 \ 1 scan0347 | |
| Invoice from S. Smith & Sons (M.A.) Ltd for a thermostat and a request for payment instructions. | 15th Dec 1937 | Box 156 \ 1 scan0348 | |
| Request to fit a thermostat scheme to a B.23.AE car. | 16th Dec 1937 | Box 156 \ 1 scan0349 | |
| Design considerations for the Bentley 50 thermostat and fan drive system. | 17th Dec 1937 | Box 156 \ 1 scan0350 | |
| Water flow arrangement for a project engine with a conventional valve layout. | 17th Dec 1937 | Box 156 \ 1 scan0351 | |
| Requesting the order of a thermostat unit and related parts for 'M' series Bentley cars. | 17th Dec 1937 | Box 156 \ 1 scan0352 | |
| Letter to The British Thermostat Co. Ltd. requesting a sample thermostat. | 17th Dec 1937 | Box 156 \ 1 scan0353 | |
| Letter from The British Thermostat Co. Ltd. enclosing Drawing No. BGA. 3786 for a Bellows Unit. | 18th Dec 1937 | Box 156 \ 1 scan0354 | |
| Letter from S. Smith & Sons acknowledging correspondence regarding a thermostat. | 20th Dec 1937 | Box 156 \ 1 scan0355 | |
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