| Description | Date | Identifier | |
| SPONTAN automatic one-pedal gearless control system. | 21th Sep 1931 | Box 41 \ 4 Scan032 | |
| Booklet for the Spontan automatic one-pedal gearless control system for motor cars. | 21th Sep 1931 | Box 41 \ 4 Scan033 | |
| Booklet for the Spontan automatic one-pedal gearless control system for motor cars. | 21th Sep 1931 | Box 41 \ 4 Scan034 | |
| Photograph of the Spontan transmission and brake fitted to an Essex Super Six engine. | 21th Sep 1931 | Box 41 \ 4 Scan035 | |
| The Spontan automatic one-pedal gearless control system for motor cars. | 21th Sep 1931 | Box 41 \ 4 Scan036 | |
| Booklet describing the operation and benefits of the 'Spontan' single-pedal automatic gear system. | 21th Sep 1931 | Box 41 \ 4 Scan037 | |
| Description of the principal parts and function of the Spontan transmission system, including a diagram. | 21th Sep 1931 | Box 41 \ 4 Scan038 | |
| Technical description of the Spontan roller clutch mechanism and its operation. | 21th Sep 1931 | Box 41 \ 4 Scan039 | |
| Technical description and theoretical considerations of the 'Spontan' transmission system. | 21th Sep 1931 | Box 41 \ 4 Scan040 | |
| Explanation with diagrams of torque impulses and the smoothening action of flywheels and pendulum wheels. | 21th Sep 1931 | Box 41 \ 4 Scan041 | |
| Technical description and analysis of the 'Spontan' transmission system, detailing its operation and performance characteristics with graphs. | 21th Sep 1931 | Box 41 \ 4 Scan042 | |
| Detailed description and explanation of the Spontan transmission system, including a diagram. | 21th Sep 1931 | Box 41 \ 4 Scan043 | |
| Description of a damping flywheel assembly and its components, illustrated with diagrams and a photograph of the vehicle interior. | 21th Sep 1931 | Box 41 \ 4 Scan044 | |
| Pages from a manual describing the 'Spontan' transmission system's components and operation. | 21th Sep 1931 | Box 41 \ 4 Scan045 | |
| Explanation of the reversing sleeves, clutch rollers, and braking mechanism with associated diagrams. | 21th Sep 1931 | Box 41 \ 4 Scan046 | |
| Two-page description of the operation and features of the Spontan Braking System. | 21th Sep 1931 | Box 41 \ 4 Scan047 | |
| Description of the Spontan braking system and independent hand brake, with accompanying diagrams. | 21th Sep 1931 | Box 41 \ 4 Scan048 | |
| Detailed description of the Spontan braking system, its operation, cooling, and interaction with other components. | 21th Sep 1931 | Box 41 \ 4 Scan049 | |
| The operation, advantages, and development of the 'Spontan' braking system and transmission. | 21th Sep 1931 | Box 41 \ 4 Scan050 | |
| Printer's mark on the cover or end page of a document, printed in Stockholm. | 21th Sep 1931 | Box 41 \ 4 Scan051 | |
| Request for comments on a proposed modification to valve covers, including a hand-drawn sketch. | 27th Sep 1919 | Box 41 \ 4 Scan052 | |
| Technical memo concerning parts and modifications for the American Model, specifically related to pipes and silencers. | 27th Sep 1919 | Box 41 \ 4 Scan053 | |
| Policy for manufacturing right and left hand chassis for the American market. | 31th Oct 1919 | Box 41 \ 4 Scan054 | |
| Decision by Mr. Royce to eliminate the use of specific steel castings on the chassis. | 22th May 1920 | Box 41 \ 4 Scan055 | |
| The Swan Inlet Manifold, attaching a copy of a letter and an S.A.E. Journal extract. | 11th Mar 1924 | Box 41 \ 4 Scan056 | |
| Letter discussing the Swan Inlet Manifold, suggesting experiments based on its success in Buick cars. | 26th Feb 1924 | Box 41 \ 4 Scan057 | |
| Modifications to the exhaust system silencer for American cars. | 16th Sep 1925 | Box 41 \ 4 Scan058 | |
| Steering issues on Springfield chassis models, particularly related to low-pressure tyres and steering gear modifications. | 8th Aug 1927 | Box 41 \ 4 Scan059 | |
| Technical report on brake mechanism clanking and exhaust banging issues. | 8th Aug 1927 | Box 41 \ 4 Scan060 | |
| Continued document discussing the benefits of an engine governor and throttle system. | 9th Aug 1929 | Box 41 \ 4 Scan061 | |
| Letter from Rolls Royce of America detailing a design simplification for a silencer to reduce rattles and production cost. | 9th Aug 1929 | Box 41 \ 4 Scan062 | |
| Design considerations for post-war chassis, including hydraulic dampers, tyre sizes, and bodywork. | 3rd Oct 1916 | Box 41 \ 4 Scan063 | |
| Proposal to purchase two second-hand car bodies for 'After the War' chassis. | 11th Oct 1916 | Box 41 \ 4 Scan064 | |
| Whether to use new or second-hand bodies for the experimental 'After the War' chassis. | 12th Oct 1916 | Box 41 \ 4 Scan065 | |
| Letter regarding the search for a suitable car body for an 'After the War Chassis'. | 26th Oct 1916 | Box 41 \ 4 Scan066 | |
| Requesting a photograph or drawing of a Barker small four-seater body for an experimental chassis, to be sent to Mr. Royce for approval. | 28th Oct 1916 | Box 41 \ 4 Scan067 | |
| Enclosing a drawing of a torpedo body for an experimental chassis. | 8th Nov 1916 | Box 41 \ 4 Scan068 | |
| Blueprint of a two-seater open-top car with dimensional details. | 7th Jan 1918 | Box 41 \ 4 Scan069 | |
| Listing extra specifications and prices for a car body from Holmes Bros. Ltd. | 7th Jan 1918 | Box 41 \ 4 Scan070 | |
| Letter from Holmes Brothers Ltd. regarding the cost and delivery of an open touring body. | 9th Dec 1918 | Box 41 \ 4 Scan071 | |
| Limousine body for an experimental chassis, forwarding a letter from coachbuilder Barkers. | 25th Jan 1919 | Box 41 \ 4 Scan072 | |
| Letter from coachbuilder Barker & Co. Ltd. offering alternative limousine bodies for an experimental chassis. | 9th Jan 1919 | Box 41 \ 4 Scan073 | |
| Bodies for experimental cars, arranging an inspection for one and suggesting the search for another. | 20th Oct 1919 | Box 41 \ 4 Scan074 | |
| Letter from coachbuilders Barker & Co. offering four second-hand bodies for sale. | 21th Nov 1919 | Box 41 \ 4 Scan075 | |
| Letter to Barker & Co. Ltd. requesting a price for an Angus-Sanderson Torpedo 5-seater car body. | 22th Nov 1919 | Box 41 \ 4 Scan076 | |
| Letter from coachbuilder Barker & Co. quoting a price for an Angus Sanderson Body. | 24th Nov 1919 | Box 41 \ 4 Scan077 | |
| Letter from coachbuilders Barker & Co. regarding the purchase of a secondhand Torpedo Body. | 9th Dec 1919 | Box 41 \ 4 Scan078 | |
| Modifications and pricing for fitting an Angus Sanderson body with a new scuttle. | 2nd Dec 1919 | Box 41 \ 4 Scan079 | |
| Proposed alterations for American cars, focusing on luggage carriers and rear spring shackles. | 2nd Dec 1919 | Box 41 \ 4 Scan080 | |
| The body design for an experimental car, comparing long and short chassis options and considering coachbuilders. | 5th Dec 1919 | Box 41 \ 4 Scan081 | |
| Letter to Barkers (Coachbuilders) arranging the collection of a purchased Angus-Sanderson Body. | 30th Dec 1919 | Box 41 \ 4 Scan082 | |
| Letter from coachbuilders Barker & Co. regarding the collection and temporary fitting of an Angus Sanderson body to a chassis. | 2nd Jan 1920 | Box 41 \ 4 Scan083 | |
| Letter from coachbuilder Barker & Co. confirming the temporary fitting of an Angus Sanderson (Torpedo) body to a chassis. | 8th Jan 1920 | Box 41 \ 4 Scan084 | |
| Requesting a sketch of the dashboard dimensions for the 10,000-miles car to avoid delays with the coachbuilder. | 14th Jan 1920 | Box 41 \ 4 Scan085 | |
| The testing of cars with covered bodies and plans for building new experimental chassis. | 1st Feb 1920 | Box 41 \ 4 Scan086 | |
| Testing of car bodies like the Cabriolet and novelties required for American manufacture. | 26th Apr 1917 | Box 41 \ 4 Scan087 | |
| Establishing a new rule for testing cars with landaulet bodies and a full load of luggage and passengers. | 9th Feb 1920 | Box 41 \ 4 Scan088 | |
| Requesting the number of extra landaulet bodies required for testing chassis before standardisation. | 23th Feb 1920 | Box 41 \ 4 Scan089 | |
| From CJ to EH regarding the requirement for testing chassis on fully loaded landaulet bodies. | 23th Feb 1920 | Box 41 \ 4 Scan090 | |
| Instructions for testing and sourcing a suitable Landaulet Body. | 25th Feb 1920 | Box 41 \ 4 Scan091 | |
| Telephone message transcript regarding the potential purchase of a Landaulet Body. | 19th Feb 1920 | Box 41 \ 4 Scan092 | |
| Copy of a telegram concerning the availability of a landaulette body. | 18th Feb 1920 | Box 41 \ 4 Scan093 | |
| Arrangements to inspect and alter a Landaulette body for an experimental car. | 25th Feb 1920 | Box 41 \ 4 Scan094 | |
| The requirement for a chassis to be sent to coachbuilders Barkers for a Saloon Body for 10,000-mile trials. | 26th Feb 1920 | Box 41 \ 4 Scan095 | |
| Requirement for Landaulet bodies to be fitted to experimental cars for passenger comfort testing. | 27th Feb 1920 | Box 41 \ 4 Scan096 | |
| Proposal for six experimental cars, detailing their configuration, testing plan, body types, and estimated costs. | 27th Feb 1920 | Box 41 \ 4 Scan097 | |
| Short memo about a potential cabriolet body for an experimental car. | 25th Feb 1920 | Box 41 \ 4 Scan098 | |
| Options for procuring new and secondhand landaulette and cabriolet bodies for experimental cars. | 2nd Mar 1920 | Box 41 \ 4 Scan099 | |
| Requirement and acquisition of Landaulet bodies for testing experimental cars. | 27th Mar 1920 | Box 41 \ 4 Scan100 | |
| Proposal for the allocation, testing, and body types for six experimental cars, including considerations for an American chassis model. | 27th Feb 1920 | Box 41 \ 4 Scan101 | |
| The purchase of a Cabriolet body from Barkers and ordering a new Landaulette body for experimental cars. | 6th Mar 1920 | Box 41 \ 4 Scan102 | |
| Ordering of a cabriolet and landaulet test bodies, including a quote from Barker's coachbuilders. | 10th Mar 1920 | Box 41 \ 4 Scan103 | |
| The loan of chassis 53-CW to the Experimental Department and its required return to the Test Department. | 12th Mar 1920 | Box 41 \ 4 Scan104 | |
| Visit to coachbuilders Fairey & Charles regarding a landaulette body for a long chassis. | 12th Mar 1920 | Box 41 \ 4 Scan105 | |
| Clarifying that the quoted £200 price for a cabriolet test body for experimental cars does not include the cost of fitting. | 12th Mar 1920 | Box 41 \ 4 Scan106 | |
| Experimental body from Fairey & Charles, referring to a previous communication. | 23th May 1919 | Box 41 \ 4 Scan107 | |
| Query regarding what is included in the £200 price for a Cabriolet Body from Messrs. Barkers for an experimental car. | 15th Mar 1920 | Box 41 \ 4 Scan108 | |
| Requesting the urgent return of chassis 53-CW from the Test/Experimental Department. | 15th Mar 1920 | Box 41 \ 4 Scan109 | |
| Urgent need for chassis 53-CW to be returned from the Experimental Department for delivery to its owner. | 13th Mar 1920 | Box 41 \ 4 Scan110 | |
| The prompt return of Test Department chassis 53-CW. | 5th Mar 1920 | Box 41 \ 4 Scan111 | |
| Requesting a delivery update for chassis 53 CW, currently in the Experimental Department, due to owner pressure. | 13th Mar 1920 | Box 41 \ 4 Scan112 | |
| Potential purchase of a second-hand car body. | 15th Mar 1920 | Box 41 \ 4 Scan113 | |
| Inquiry regarding interest in a second-hand Barker Landaulette body from a 1913 chassis. | 12th Mar 1920 | Box 41 \ 4 Scan114 | |
| Request for a cabriolet body specification from Barker's for experimental cars. | 16th Mar 1920 | Box 41 \ 4 Scan115 | |
| Fitting of a Cabriolet body by Barkers to an experimental chassis and inquiring about its completion date. | 17th Mar 1920 | Box 41 \ 4 Scan116 | |
| Fitting cabriolet and saloon bodies to experimental car chassis and associated delays. | 18th Mar 1920 | Box 41 \ 4 Scan117 | |
| Fittings included in the price for a Test Body from Barkers. | 11th Nov 1920 | Box 41 \ 4 Scan118 | |
| Internal request to order a second-hand Cabriolet body and its parts for £200. | 19th Mar 1920 | Box 41 \ 4 Scan119 | |
| Declining the offer of a second-hand Landaulet body. | 19th Mar 1920 | Box 41 \ 4 Scan120 | |
| Handover of chassis 53-CW from the Experimental Department back to the Test Department due to delivery concerns. | 25th Mar 1920 | Box 41 \ 4 Scan121 | |
| Chassis 53-CW, following up on a request for information for the Sales Department. | 26th Mar 1920 | Box 41 \ 4 Scan122 | |
| Overdue chassis that needs to be returned to the Test Department, which is now five months late. | 29th Mar 1920 | Box 41 \ 4 Scan123 | |
| Drawing and quotation from coachbuilders Fairey & Charles for a Landaulet body for a long experimental chassis. | 10th Apr 1920 | Box 41 \ 4 Scan124 | |
| Complaints about cars being driven too fast and unsafely within the works yards. | 14th Apr 1920 | Box 41 \ 4 Scan125 | |
| Notice regarding cars speeding on works premises, outlining new rules and the threat of instant dismissal. | 1st Apr 1920 | Box 41 \ 4 Scan126 | |
| Requesting assistance in sourcing a Landaulette body for chassis testing. | 21th Apr 1920 | Box 41 \ 4 Scan127 | |
| Request for an estimate and specification for a Landaulet Body from Fairey & Charles. | 21th Apr 1920 | Box 41 \ 4 Scan128 | |
| Difficulties with supplier Fairey & Charles for a Landaulet body, and getting a drawing from Hoopers instead. | 6th May 1920 | Box 41 \ 4 Scan129 | |
| Letter discussing bodywork options and specifications for an Experimental Landaulet Car. | 17th May 1920 | Box 41 \ 4 Scan130 | |
| Loan of a car to Mr. L. Rapson and advising against using an Experimental car for competitive trials. | 27th May 1920 | Box 41 \ 4 Scan131 | |
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