| Description | Date | Identifier | |
| List of factors that do not appear to affect tyre noise. | 7th Oct 1935 | Box 30 \ 5 Scan151 | |
| Investigations into tyre noise on a Phantom III car using cast iron drums. | 8th Nov 1935 | Box 30 \ 5 Scan152 | |
| Letter from the India Tyre & Rubber Company Ltd. regarding a confidential enclosure. | 8th Nov 1935 | Box 30 \ 5 Scan153 | |
| Comparison document detailing the circumference and performance metrics of India Super and Speed Special tyres. | 11th Nov 1935 | Box 30 \ 5 Scan154 | |
| Letter to The Earl of Rothes at The India Tyre & Rubber Co. arranging a meeting about a tyre noise complaint. | 13th Nov 1935 | Box 30 \ 5 Scan155 | |
| Super India Tyres for a Bentley Trials Car chassis. | 19th Nov 1935 | Box 30 \ 5 Scan156 | |
| Letter from India Tyre & Rubber Co. arranging a meeting, discussing a steel body for the Phantom III chassis and Bentley tyres. | 20th Nov 1935 | Box 30 \ 5 Scan157 | |
| Letter from Park Ward & Co. Ltd. to The Earl of Rothes discussing the construction of a steel body on a Rolls-Royce chassis. | 18th Nov 1935 | Box 30 \ 5 Scan158 | |
| The use of Swiss alloy for car bodies, challenges with Bentley chassis, and cooperation between coachbuilders. | 18th Nov 1935 | Box 30 \ 5 Scan159 | |
| The final page of a letter from Park Ward & Co. | 22th Nov 1935 | Box 30 \ 5 Scan160 | |
| Responding to queries about India 'Super' Tyres with findings and measurements. | 22th Nov 1935 | Box 30 \ 5 Scan161 | |
| Letter to The Earl of Rothes arranging a meeting and lunch for Friday the 29th to discuss the body situation. | 25th Nov 1935 | Box 30 \ 5 Scan162 | |
| Letter from India Tyre & Rubber Company Ltd. confirming a lunch meeting in Derby. | 26th Nov 1935 | Box 30 \ 5 Scan163 | |
| Letter from the India Tyre & Rubber Company Ltd. concerning the dispatch of various trial tyre sets, including Aero Cushion tyres. | 2nd Dec 1935 | Box 30 \ 5 Scan164 | |
| Order for 5 Aero Cushion 6-ply Tyres from India Tyre & Rubber Co. Ltd. | 3rd Dec 1935 | Box 30 \ 5 Scan165 | |
| Letter from India Tyre & Rubber Company discussing tyre suitability, sizes, and potential trials. | 3rd Dec 1935 | Box 30 \ 5 Scan166 | |
| Inter-departmental memo discussing various tyre options, weights, and tests for a Bentley. | 2nd Dec 1935 | Box 30 \ 5 Scan167 | |
| Table of tyre specifications listing cross-section, outer diameter, effective radius, and weight. | 5th Dec 1935 | Box 30 \ 5 Scan168 | |
| Letter concerning the dispatch of four part-worn 7.00-18 INDIA Super covers and Black Tubes from a Phantom-Three chassis. | 5th Dec 1935 | Box 30 \ 5 Scan169 | |
| Requesting an order to be passed to the India Tyre & Rubber Co. for four Super Covers & Tubes. | 6th Dec 1935 | Box 30 \ 5 Scan170 | |
| Letter to The India Tyre & Rubber Co. Ltd. concerning the weight of a Dunlop Bentley Wheel. | 6th Dec 1935 | Box 30 \ 5 Scan171 | |
| Specification sheet detailing the weights of various tyres and wheels. | 20th Dec 1935 | Box 30 \ 5 Scan172 | |
| Explaining how a weight difference in a wheel assembly is accounted for by balancing weights. | 9th Dec 1935 | Box 30 \ 5 Scan173 | |
| Letter from India Tyre & Rubber Company regarding the weight of Bentley wheels. | 9th Dec 1935 | Box 30 \ 5 Scan174 | |
| Tyres sent to the Test Department for use on a Phantom III testing chassis. | 11th Dec 1935 | Box 30 \ 5 Scan175 | |
| List of various tyres and tubes sent to the Test Department for evaluation. | 11th Dec 1935 | Box 30 \ 5 Scan176 | |
| The supply of tyres from the India Tyre Company for a 20/25 HP model. | 16th Dec 1935 | Box 30 \ 5 Scan177 | |
| Investigations into tyre noise on the Phantom III model, detailing various experiments. | 18th Dec 1935 | Box 30 \ 5 Scan178 | |
| Car noise when driving over setts, comparing tyre types and proposing tests with rubber body mountings. | 19th Dec 1935 | Box 30 \ 5 Scan179 | |
| Responding to a query about the supply of India tyres for the 20/25 HP model. | 19th Dec 1935 | Box 30 \ 5 Scan180 | |
| Letter to The Earl of Rothes at The India Tyre & Rubber Co. Ltd. confirming the weight of a 16' wheel. | 21th Dec 1935 | Box 30 \ 5 Scan181 | |
| Invoice for experimental tyres and tubes, with queries about their prior use on demonstration cars. | 24th Dec 1935 | Box 30 \ 5 Scan182 | |
| Letter to The Earl of Rothes at The India Tyre & Rubber Co. Ltd. regarding the unwrapped condition of received tyres. | 30th Dec 1935 | Box 30 \ 5 Scan183 | |
| Enquiry from the India Tyre & Rubber Company regarding potential damage to a tyre fitted to a Bentley. | 23th Dec 1935 | Box 30 \ 5 Scan184 | |
| Letter from India Tyre & Rubber Co. regarding a set of wheels for testing and tyre wear on the 4¼ litre Bentley. | 8th Jan 1937 | Box 30 \ 5 Scan185 | |
| Page two of a letter from India Tyre & Rubber Co. to W.A. Robotham discussing car stability. | 8th Jan 1937 | Box 30 \ 5 Scan186 | |
| Despatch of 5 Bentley 4x17 wheels to The India Tyre Co.Ltd., Scotland. | 13th Jan 1937 | Box 30 \ 5 Scan187 | |
| Letter to The India Tyre & Rubber Co., Ltd. regarding the despatch of Bentley wheels for Mr. Summer's car. | 13th Jan 1937 | Box 30 \ 5 Scan188 | |
| Non-corrosive treatments like Cadmium plating and anodic treatment for various metal parts. | 1st Nov 1927 | Box 30 \ 6 Scan001 | |
| Experiments with various treatments, including anodic, cadmium, and lead plating, to prevent aluminium screw threads from seizing. | 9th Dec 1927 | Box 30 \ 6 Scan002 | |
| Laboratory report on tests to determine the effectiveness of low-temperature heat-treatment in cadmium plating. | 17th Dec 1927 | Box 30 \ 6 Scan003 | |
| On an Inspector's Report form discussing the 'Economy Fetish' of 10,000 miles versus real-world road tests. | 7th Dec 1927 | Box 30 \ 6 Scan004 | |
| Brittleness of springs caused by cadmium plating and suggesting heat treatment as a solution. | 29th Dec 1927 | Box 30 \ 6 Scan005 | |
| Properties and testing of chromium-plated road springs. | 31th Dec 1927 | Box 30 \ 6 Scan006 | |
| The benefits of plating road springs to improve suspension, prolong life, and reduce squeaking. | 2nd Jan 1928 | Box 30 \ 6 Scan007 | |
| Plating of springs, including issues with brittleness and the advantages of American spring lubrication methods. | 2nd Jan 1928 | Box 30 \ 6 Scan008 | |
| Arguing against the proposal for plating road springs due to the risk of brittleness in the steel. | 3rd Jan 1928 | Box 30 \ 6 Scan009 | |
| Suitability of different parts for testing chromium plating, specifically rejecting valve springs and questioning the use of road springs. | 1st Jan 1928 | Box 30 \ 6 Scan010 | |
| Clarifying the reasoning for testing the plating process on valve springs before applying it to road springs. | 6th Jan 1928 | Box 30 \ 6 Scan011 | |
| Proposal for experiments in chromium plating specific engine and vehicle components. | 9th Jan 1928 | Box 30 \ 6 Scan012 | |
| Potential improvements for 40/50 HP water pumps, focusing on the friction drive and glands. | 9th Jan 1928 | Box 30 \ 6 Scan013 | |
| Page two of a memo discussing the results of a device test and suggesting material improvements. | 10th Jan 1928 | Box 30 \ 6 Scan014 | |
| Implementation of Chromium and Cadmium Plating, addressing perceived delays. | 10th Jan 1928 | Box 30 \ 6 Scan015 | |
| Recommending cadmium plating for steel control parts and supercharger diffuser rings on aero engines to prevent rusting. | 11th Jan 1928 | Box 30 \ 6 Scan016 | |
| Determining the necessity of dimensional allowances for cadmium plating on control parts and diffuser vanes. | 13th Jan 1928 | Box 30 \ 6 Scan017 | |
| Proposal for testing chromium-plated springs for hydrogen brittleness and comparative results. | 13th Mar 1928 | Box 30 \ 6 Scan018 | |
| Standardisation of a Cadmium plated and stove-enamelled external finish for aero engines. | 14th Mar 1928 | Box 30 \ 6 Scan019 | |
| Application of centralised chassis lubrication for the India 3 model, including battery suspension and brake gear. | 17th Mar 1923 | Box 30 \ 6 Scan020 | |
| Meeting with Mr. Einstein regarding his electro-chemical deposition metalising process. | 3rd Apr 1928 | Box 30 \ 6 Scan021 | |
| Mr. Einstein's proposal for a metalizing factory and a suggestion for a trial order on a cylinder water jacket. | 1st Apr 1928 | Box 30 \ 6 Scan022 | |
| Test results for a chromium-plated water pump spindle, noting an improvement over the Staybright spindle. | 27th Apr 1928 | Box 30 \ 6 Scan023 | |
| Request to prepare and cadmium plate standard front road springs for a bump test. | 1st May 1928 | Box 30 \ 6 Scan024 | |
| Copy of a telegram suggesting to chromium plate the bore of a blade rod. | 8th Jun 1928 | Box 30 \ 6 Scan025 | |
| Testing cadmium-plated road springs, detailing wear patterns, life expectancy, and recommendations for further trials. | 26th Jun 1928 | Box 30 \ 6 Scan026 | |
| Request for cadmium plating of front and rear road springs with specified unloaded camber details. | 29th Jun 1928 | Box 30 \ 6 Scan027 | |
| Instructions regarding the cadmium plating of a car's springs at the Works. | 4th Jul 1928 | Box 30 \ 6 Scan028 | |
| Test report on a centralised lubrication scheme, noting a cracked pipe and the performance of a cadmium-plated road spring. | 7th Jul 1928 | Box 30 \ 6 Scan029 | |
| Potential improvements to vehicle riding qualities, covering tyres, springs, and shock dampers. | 23th Jul 1928 | Box 30 \ 6 Scan030 | |
| The correct road springs for the 17-EX experimental car, including specifications and sourcing instructions. | 24th Jul 1928 | Box 30 \ 6 Scan031 | |
| Request to have the new type rear springs cadmium plated before they are fitted. | 24th Aug 1928 | Box 30 \ 6 Scan032 | |
| New scheme for rear springs, requesting a standard pair be cadmium plated instead of using a special type. | 27th Aug 1928 | Box 30 \ 6 Scan033 | |
| Requesting the inspection of cadmium-plated front springs for testing purposes. | 1st Sep 1928 | Box 30 \ 6 Scan034 | |
| Clarifying the experimental status of cadmium plating for springing and requesting its availability for standard production. | 22th Sep 1928 | Box 30 \ 6 Scan035 | |
| Non-standardisation and issues with cadmium plating on springs. | 24th Sep 1928 | Box 30 \ 6 Scan036 | |
| Requesting the cadmium plating and re-fitting of 1600 lbs. rear springs for the 10-EX car. | 25th Sep 1923 | Box 30 \ 6 Scan037 | |
| Proposal to chromium plate an experimental car to gain practical experience with the finish and to test an external supplier. | 27th Sep 1928 | Box 30 \ 6 Scan038 | |
| Clarifying a point about the standard specification of cadmium-plated springs. | 24th Sep 1928 | Box 30 \ 6 Scan039 | |
| Query regarding instructions for cadmium plating special road springs on chassis GKM-33. | 28th Sep 1928 | Box 30 \ 6 Scan040 | |
| Suggestion to use chromium plating on a new car, recommending the 'India-4' model. | 28th Sep 1928 | Box 30 \ 6 Scan041 | |
| The use of chromium plating on one of two new car models being built. | 28th Sep 1928 | Box 30 \ 6 Scan042 | |
| Letter to Solex Ltd. arranging a visit to their Paris laboratory and discussing carburetter and crankshaft design. | 29th Sep 1928 | Box 30 \ 6 Scan043 | |
| The unauthorized cadmium plating of springs on chassis GKM-33 and the halt of this practice pending standardization. | 2nd Oct 1928 | Box 30 \ 6 Scan044 | |
| Recommendation for cadmium plating on Phantom chassis parts based on long-term testing. | 1st Oct 1928 | Box 30 \ 6 Scan045 | |
| Parts list for the Water Pump Drive and Governor assembly of an engine unit. | 1st Oct 1928 | Box 30 \ 6 Scan046 | |
| Parts list for an ignition distributor, clutch, and slipper wheels & spring drive. | 1st Oct 1928 | Box 30 \ 6 Scan047 | |
| Parts list for the complete servo linkage assembly. | 1st Oct 1928 | Box 30 \ 6 Scan048 | |
| Parts list for the servo shaft, fittings, and associated pedals. | 1st Oct 1928 | Box 30 \ 6 Scan049 | |
| List of drawing numbers and part names for front and rear brakes, with additional notes on other vehicle components. | 8th Oct 1928 | Box 30 \ 6 Scan050 | |
| Standardisation of cadmium plating and the bedding of leaves for road springs. | 8th Oct 1928 | Box 30 \ 6 Scan051 | |
| The availability and application of chromium plating for exterior car fittings, including the radiator. | 10th Oct 1928 | Box 30 \ 6 Scan052 | |
| Suggesting modifications to a lightened clutch, flywheel and serrated universal joint to improve lubrication. | 10th Oct 1928 | Box 30 \ 6 Scan053 | |
| Provision of a chromium-plated radiator to allow for the fitting of other chromium-plated parts. | 17th Oct 1928 | Box 30 \ 6 Scan054 | |
| Instructions for chromium plating parts for 'SS' cars. | 17th Oct 1928 | Box 30 \ 6 Scan055 | |
| Issues with chromium plating and recommending to continue with nickel plating as the standard finish. | 18th Oct 1928 | Box 30 \ 6 Scan056 | |
| Arranging for an experimental 20 HP car to have its nickel parts chromium plated. | 19th Oct 1928 | Box 30 \ 6 Scan057 | |
| Process and requirements for chromium plating on nickel silver for various car parts. | 20th Oct 1928 | Box 30 \ 6 Scan058 | |
| Difficulties and commercial viability of chromium plating on chassis. | 30th Oct 1928 | Box 30 \ 6 Scan059 | |
| Investigation into mysterious breakages of cadmium plated screws, identifying hydrogen embrittlement as the cause and proposing heat treatment as a remedy. | 9th Nov 1928 | Box 30 \ 6 Scan060 | |
| From 'ROY' discussing an offer from Harcourts Ltd for experimental chrome plating on components like crankshafts. | 21th Nov 1928 | Box 30 \ 6 Scan061 | |
| Instruction prohibiting the sandblasting of pipes, particularly copper pipes, as a method of cleaning. | 21th Nov 1928 | Box 30 \ 6 Scan062 | |
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