| Description | Date | Identifier | |
| Secret memo regarding arrangements to collect a Hispano car from Barkers. | 13th Nov 1923 | Box 22 \ 1 Scan019 | |
| Testing and modifications of a 4-wheel brake system. | 14th Nov 1923 | Box 22 \ 1 Scan020 | |
| Comparing the weights and braking characteristics of two 40/50 HP cars and a Hispano Suiza. | 15th Nov 1923 | Box 22 \ 1 Scan021 | |
| Request to obtain an instruction book for a Hispano car, either permanently or on loan. | 16th Nov 1923 | Box 22 \ 1 Scan022 | |
| Clarifying a request for information on pedal pressure for braking, referencing Hispano and Isotta. | 17th Nov 1923 | Box 22 \ 1 Scan023 | |
| Extract from a letter by Barker & Co. Ltd regarding a delay in handing over a Hispano Suiza car. | 19th Nov 1923 | Box 22 \ 1 Scan024 | |
| Initial report on the Hispano car, outlining its defects and design characteristics compared to an RR car. | 21th Nov 1923 | Box 22 \ 1 Scan025 | |
| Development and issues of a front-wheel braking system, proposing a new torque member design. | 28th Nov 1923 | Box 22 \ 1 Scan026 | |
| Experiment measuring pivot movement on a Hispano Suiza car with front brakes applied. | 26th Nov 1923 | Box 22 \ 1 Scan027 | |
| Inquiring about the petrol consumption of the Hispano car for comparison. | 28th Nov 1923 | Box 22 \ 1 Scan028 | |
| Investigation into the Hispano's bonnet louvre design and its effect on engine noise and water temperature. | 28th Nov 1923 | Box 22 \ 1 Scan029 | |
| The particulars of brakes on a Hispano car. | 29th Nov 1923 | Box 22 \ 1 Scan030 | |
| Graph showing axle movement under load for a 'Hispano' model in two positions. | 29th Nov 1923 | Box 22 \ 1 Scan031 | |
| Design drawing for a Hispano Brake Shoe with measurements. | 1st Feb 1924 | Box 22 \ 1 Scan032 | |
| Hand-drawn diagram showing the layout and dimensions of a Hispano front brake system. | 1st Feb 1924 | Box 22 \ 1 Scan033 | |
| Schematic diagram of the Hispano rear brake operating mechanism, showing levers, cams, and dimensions. | 24th Jan 1923 | Box 22 \ 1 Scan034 | |
| Diagram of the Hispano front wheel brake linkage system with an associated movement table. | 29th Nov 1923 | Box 22 \ 1 Scan035 | |
| Referencing a Hispano car. | 29th Nov 1923 | Box 22 \ 1 Scan036 | |
| Hand-drawn sketch with dimensions of a Hispano Brake Shoe. | 21th Jan 1929 | Box 22 \ 1 Scan037 | |
| Diagram illustrating the linkage and operation of a Hispano rear brake system. | 21th Jan 1929 | Box 22 \ 1 Scan038 | |
| Drawing illustrating the Hispano front wheel brake linkage mechanism. | 25th Nov 1923 | Box 22 \ 1 Scan039 | |
| Technical drawing of a Hispano front brake with annotations and dimensions. | 25th Nov 1923 | Box 22 \ 1 Scan040 | |
| From R. to H.S. requesting an investigation into front road spring breakages and steering gear flexibility. | 30th Nov 1923 | Box 22 \ 1 Scan041 | |
| Requesting further particulars on Hispano-Suiza brakes, specifically the cam position and 'servo' mechanism. | 1st Dec 1923 | Box 22 \ 1 Scan042 | |
| Petrol consumption of a Hispano car. | 12th Dec 1923 | Box 22 \ 1 Scan043 | |
| Consumption data for an R.R. vehicle under conditions similar to those of a Hispano car. | 3rd Dec 1923 | Box 22 \ 1 Scan044 | |
| Comparing the fuel consumption of a Hispano and a standard new 40/50 chassis. | 4th Dec 1923 | Box 22 \ 1 Scan045 | |
| Issues with the floating fulcrum brake, detailing tests to reduce jaggering. | 12th Jul 1923 | Box 22 \ 1 Scan046 | |
| Tests conducted on the Epicyclic Equalizer, Hispano brakes, and Pedal Pressure. | 1st Dec 1923 | Box 22 \ 1 Scan047 | |
| Brief memo regarding the licence for a Hispano car. | 7th Dec 1923 | Box 22 \ 1 Scan048 | |
| Request for the return of 'RAC' and 'AA' badges belonging to the previous owner of a Hispano-Suiza car. | 11th Dec 1923 | Box 22 \ 1 Scan049 | |
| Request for a new oversized piston for a Hispano car, Chassis No. 10482, and confirmation of sending two badges. | 12th Dec 1923 | Box 22 \ 1 Scan050 | |
| List of tools for a Hispano Suiza vehicle, categorized by storage location. | 12th Dec 1923 | Box 22 \ 1 Scan051 | |
| Continued list of tools and spare parts. | 20th Dec 1923 | Box 22 \ 1 Scan052 | |
| Requesting the return of servo parts and a 'Braking' file, following a Sales request to test a Hispano car. | 20th Dec 1923 | Box 22 \ 1 Scan053 | |
| Follow-up memo requesting an update on obtaining a new piston for a Hispano car. | 20th Dec 1923 | Box 22 \ 1 Scan054 | |
| Confirming the decision to manufacture the piston for the Hispano car in-house. | 28th Dec 1923 | Box 22 \ 1 Scan055 | |
| From CJ to Hs discussing plans to test brakes on a Hispano and a 40/50 HP chassis, including a proposed road test in France. | 28th Dec 1923 | Box 22 \ 1 Scan056 | |
| Post office telegram regarding the return of a Hispano servo part. | 16th Jan 1924 | Box 22 \ 1 Scan057 | |
| The dispatch of delayed Hispano servo parts and the return of a file on braking. | 1st Jan 1924 | Box 22 \ 1 Scan058 | |
| Enquiry from Barkers about receiving Hispano and Isotta-Fraschini cars for sale. | 3rd Jan 1924 | Box 22 \ 1 Scan059 | |
| Letter arranging a car road test and comparison with a Hispano car's brakes. | 15th Jan 1924 | Box 22 \ 1 Scan060 | |
| Request to urgently obtain a 3-month license for a Hispano car, number XM.3790. | 15th Jan 1924 | Box 22 \ 1 Scan061 | |
| Hispano car, detailing issues with the clutch, engine, and steering. | 16th Jan 1924 | Box 22 \ 1 Scan062 | |
| Calculations and diagram for the Goshawk Clutch. | 16th Jan 1924 | Box 22 \ 1 Scan063 | |
| Drawing and calculation sheet for the Hepano Clutch and Bingo operating mechanism. | 16th Jan 1924 | Box 22 \ 1 Scan064 | |
| Technical drawing showing multiple views and cross-sections of an axle pivot. | 16th Jan 1924 | Box 22 \ 1 Scan065 | |
| Technical drawing showing three views of a cylinder block. | 16th Jan 1924 | Box 22 \ 1 Scan066 | |
| Arrangement drawing of a clutch, featuring a top half sectional view and a front view. | 16th Jan 1924 | Box 22 \ 1 Scan067 | |
| Diagram showing the distance between the tyre centre and pivot pin centre when in contact with the road. | 16th Jan 1924 | Box 22 \ 1 Scan068 | |
| Engineering drawing of a connecting rod showing plan, section, and end views with dimensions. | 16th Jan 1924 | Box 22 \ 1 Scan069 | |
| Detailed engineering drawing of a clutch assembly, showing multiple views and dimensions. | 8th Jan 1924 | Box 22 \ 1 Scan070 | |
| Detailed technical drawing of a crankshaft with dimensional annotations. | 8th Jan 1924 | Box 22 \ 1 Scan071 | |
| Confirming travel arrangements to Derby, with the intention of bringing a Hispano car. | 16th Jan 1924 | Box 22 \ 1 Scan072 | |
| Hispano test run, observations on the driver's controls, and alternative travel plans due to a potential railway strike. | 18th Jan 1924 | Box 22 \ 1 Scan073 | |
| The performance and characteristics of the Hispano-Suiza four-wheel brake system. | 21th Jan 1924 | Box 22 \ 1 Scan074 | |
| Page discussing the superiority and necessity of 4-wheel brake systems for high-class cars. | 23th Jan 1924 | Box 22 \ 1 Scan075 | |
| Internal request for steering and turning circle specifications for a Hispano-Suiza. | 23th Jan 1924 | Box 22 \ 1 Scan076 | |
| Order for searchlight lamps for a Hispano-Suiza car. | 27th Jan 1924 | Box 22 \ 1 Scan077 | |
| The road testing of the brakes on a Hispano car. | 29th Jan 1924 | Box 22 \ 1 Scan078 | |
| Requesting a braking system test be arranged for a Hispano car on an incline. | 29th Jan 1924 | Box 22 \ 1 Scan079 | |
| Brake testing a 40/50 HP car with cast iron servo liners, noting noise issues and comparison to the Hispano system. | 30th Jan 1924 | Box 22 \ 1 Scan080 | |
| Calculation comparing the unit pressure on servo shoes with Hispano servo shoes. | 30th Jan 1924 | Box 22 \ 1 Scan081 | |
| Testing of Hispano brakes on a car running backwards on a gradient. | 30th Jan 1924 | Box 22 \ 1 Scan082 | |
| Letter praising the performance of a 'Type Boulogne' Hispano motor car. | 1st Feb 1924 | Box 22 \ 1 Scan083 | |
| Letter discussing the performance of a 'Type Boulogne' car, comparing it to a Hispano, and arranging a test drive. | 2nd Feb 1924 | Box 22 \ 1 Scan084 | |
| Letter discussing the performance and qualities of 'Hispano' brakes and engines compared to other vehicles. | 2nd Feb 1924 | Box 22 \ 1 Scan085 | |
| Potential test drive of a Hispano Suiza special model car. | 4th Feb 1924 | Box 22 \ 1 Scan086 | |
| Initial impressions of the new Hispano-Suiza 'Type Boulogne' and comparing its performance to Rolls-Royce cars. | 1st Feb 1924 | Box 22 \ 1 Scan087 | |
| Car's braking system and its suitability for the luxury market. | 2nd Feb 1924 | Box 22 \ 1 Scan088 | |
| Comparing Rolls Royce and Hispano cars. | 2nd Feb 1924 | Box 22 \ 1 Scan089 | |
| The hill climbing performance of a 40/50 HP car in North Devon, comparing it to a Hispano Suiza. | 12th Jul 1923 | Box 22 \ 1 Scan090 | |
| Braking tests conducted in North Devon on Porlock and Countisbury hills. | 12th Jul 1923 | Box 22 \ 1 Scan091 | |
| Comparison table of hill climbing tests in North Devon for a 40/50 HP model and a Hispano Suiza. | 12th Jul 1923 | Box 22 \ 1 Scan092 | |
| Comparison of brake tests between the E.A.C. high-speed servo and Hispano systems in North Devon. | 7th Feb 1924 | Box 22 \ 1 Scan093 | |
| Steering specifications and turning circles for a Hispano model. | 7th Feb 1924 | Box 22 \ 1 Scan094 | |
| With drawings detailing a Hispano Suiza steering mechanism. | 7th Feb 1924 | Box 22 \ 1 Scan095 | |
| Comparing the weights and specifications of Hispano and EAC.111 front brakes. | 1st Feb 1924 | Box 22 \ 1 Scan096 | |
| The condition of steel brake drum liners and a proposal to test a Hispano brake. | 1st Feb 1924 | Box 22 \ 1 Scan097 | |
| Drawing of a 15 HP front brake drum made from aluminium with a steel liner. | 1st Feb 1924 | Box 22 \ 1 Scan098 | |
| Cross-section engineering drawing of a carrier with dimensions and weight. | 1st Feb 1924 | Box 22 \ 1 Scan099 | |
| Drawing of a Hispano front shoe with dimensions and a cross-section view. | 1st Feb 1924 | Box 22 \ 1 Scan100 | |
| Drawing of a Hispano Brake Carrier made from aluminium. | 11th Feb 1924 | Box 22 \ 1 Scan101 | |
| Design and fitting of a servo system for brakes, including servo drive and pull. | 11th Feb 1924 | Box 22 \ 1 Scan102 | |
| Technical memorandum discussing improvements to brake design, including a comparison with Hispano brakes. | 11th Feb 1924 | Box 22 \ 1 Scan103 | |
| Page 3 of a typed letter discussing holding a car on a 1 in 5 gradient and 4-wheel brakes. | 11th Feb 1924 | Box 22 \ 1 Scan104 | |
| Competitor's (Hispano) remarkable acceleration and questioning whether to emulate it. | 11th Feb 1924 | Box 22 \ 1 Scan105 | |
| Field report letter detailing a road test, including notes on brake performance and travel itinerary. | 6th Feb 1924 | Box 22 \ 1 Scan106 | |
| Modifications to a low-speed brake servo and resulting pedal pressure. | 11th Feb 1924 | Box 22 \ 1 Scan107 | |
| Requesting to borrow a Hispano-Suiza 'Type Boulogne' car for performance testing at Brooklands. | 2nd Feb 1924 | Box 22 \ 1 Scan108 | |
| Weight breakdown for Hispano Suiza components including the unit, radiator, side levers and pedals. | 12th Feb 1924 | Box 22 \ 1 Scan109 | |
| Chassis modifications for a trip to the South of France and competing with a Hispano car. | 13th Feb 1924 | Box 22 \ 1 Scan110 | |
| Confirming a Hispano Suiza car has been sold and is unavailable. | 14th Feb 1924 | Box 22 \ 1 Scan111 | |
| Hispano engine, detailing its removal, weight, and comparison with an EAC engine. | 14th Feb 1924 | Box 22 \ 1 Scan112 | |
| Comparative table of road wheel Horse Power for Hispano and EAC engines at various RPMs. | 1st Feb 1924 | Box 22 \ 1 Scan113 | |
| Secret internal memo about reducing the weight of four-wheel brakes using aluminium or duralumin. | 1st Feb 1924 | Box 22 \ 1 Scan114 | |
| Power curve test data for a Hispano Suiza engine. | 19th Feb 1924 | Box 22 \ 1 Scan115 | |
| Short internal memo from 'R.' to 'H.S.' concerning an arrangement related to 'HISPANO X.4214'. | 19th Feb 1924 | Box 22 \ 1 Scan116 | |
| EAC engine test, detailing horsepower results at various RPMs. | 20th Feb 1924 | Box 22 \ 1 Scan117 | |
| Secret internal memorandum discussing three design issues: patents, steering shocks, and a heated dynamo. | 23th Feb 1924 | Box 22 \ 1 Scan118 | |
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