| Description | Date | Identifier | |
| Letter from Thos. Firth & John Brown, Ltd. regarding the design of 20 HP Flexible Road Springs. | 28th May 1931 | Box 52 \ 2 Scan283 | |
| Comparison of design specifications for five, six, and seven plate springs. | 28th May 1931 | Box 52 \ 2 Scan284 | |
| Letter detailing the specifications for 20/25 HP Front Flexible Road Springs. | 29th May 1931 | Box 52 \ 2 Scan285 | |
| Specification sheet for a 25 HP Front Road Spring. | 30th May 1931 | Box 52 \ 2 Scan286 | |
| Receipt and testing of new, cheaper road springs for the 20/25 HP and Phantom II models. | 18th Jun 1931 | Box 52 \ 2 Scan287 | |
| Specification sheet for 20/25 Hp car spring weights for Firths springs. | 6th Nov 1931 | Box 52 \ 2 Scan288 | |
| Forwarding a paper on heat treatment tests for axle springs and the fatigue resistance of spring steels. | 10th Nov 1931 | Box 52 \ 2 Scan289 | |
| Changes to the specifications of road springs for the Peregrine model. | 13th Aug 1932 | Box 52 \ 2 Scan290 | |
| The testing and comparison of Woodhead road springs against standard Firths springs on a 25HP bumper chassis. | 5th Nov 1932 | Box 52 \ 2 Scan291 | |
| Spring lubrication issues and plans for testing new Woodhead springs. | 5th Nov 1932 | Box 52 \ 2 Scan292 | |
| Use of Rolled versus Solid Eyes on axle springs for various chassis models. | 12th Nov 1932 | Box 52 \ 2 Scan293 | |
| Transmittal note for blueprints of drawings related to the 'Goshawk' II Condenser. | 29th Aug 1921 | Box 52 \ 3 Scan001 | |
| Blueprints for the 'Goshawk' II Condenser, noting the difficulty of increasing its capacity. | 1st Aug 1921 | Box 52 \ 3 Scan002 | |
| Extract discussing the specifications and advantages of a larger condenser for Goshawk battery ignition. | 27th Sep 1921 | Box 52 \ 3 Scan003 | |
| Confirming an experiment to increase the capacity of a Goshawk condenser using oiled paper dielectrics. | 25th Oct 1921 | Box 52 \ 3 Scan004 | |
| Correcting an error in the estimated volume and capacity of the Goshawk condenser. | 25th Oct 1921 | Box 52 \ 3 Scan005 | |
| The capacity of a Goshawk condenser compared to a Bosch battery ignition, and experiments with paper dielectrics. | 25th Oct 1921 | Box 52 \ 3 Scan006 | |
| Request to order tin foil and mica plates for making experimental condensers. | 5th Nov 1921 | Box 52 \ 3 Scan007 | |
| Request to arrange a supply of twin condenser paper for experimental Goshawk condensers. | 5th Nov 1921 | Box 52 \ 3 Scan008 | |
| Covering letter forwarding a quotation and a sample book for insulating paper, along with another letter, requesting further instructions. | 18th Nov 1921 | Box 52 \ 3 Scan009 | |
| Letter from Spicer Bros. Ltd. clarifying a query about the thickness of Insulating Paper. | 17th Nov 1921 | Box 52 \ 3 Scan010 | |
| Letter from The Swiss Insulating Works Ltd. providing a price for Oil Paper Tapes. | 15th Nov 1921 | Box 52 \ 3 Scan011 | |
| Progress and challenges of electrical work and material sourcing for the 'Goshawk II' project. | 21th Nov 1921 | Box 52 \ 3 Scan012 | |
| Questioning the purchase of Dubiliers condensers and suggesting design modifications for in-house production. | 21th Nov 1921 | Box 52 \ 3 Scan013 | |
| From 'R' expressing frustration over sourcing materials for condensers, such as thin paper and low hysteresis steel. | 21th Nov 1921 | Box 52 \ 3 Scan014 | |
| Letter from Rolls-Royce of America regarding battery ignition condenser tests and insulation breakdown in paper condensers. | 21th Nov 1921 | Box 52 \ 3 Scan015 | |
| Letter from the American Bosch Magneto Corporation regarding battery ignition condenser tests. | 6th Sep 1921 | Box 52 \ 3 Scan016 | |
| Page 2 of a letter from American Bosch Magneto Corporation regarding mica condenser specifications and testing. | 12th Dec 1928 | Box 52 \ 3 Scan017 | |
| The development and testing of different condenser configurations for the Goshawk ignition system. | 24th Nov 1921 | Box 52 \ 3 Scan018 | |
| Confirming a modified design for a Goshawk ignition condenser, including a quote from Mr. Royce. | 24th Nov 1921 | Box 52 \ 3 Scan019 | |
| Comparing the construction and volume of Bosch condensers with the design for the Goshawk ignition system. | 24th Nov 1921 | Box 52 \ 3 Scan020 | |
| Development of mica and paper condensers, comparing materials, sourcing, and design modifications. | 24th Nov 1921 | Box 52 \ 3 Scan021 | |
| Construction, capacity, and testing of a condenser. | 24th Nov 1921 | Box 52 \ 3 Scan022 | |
| Technical memo detailing improvements and considerations for the battery ignition system on the 'Coshawk II'. | 23th Nov 1921 | Box 52 \ 3 Scan023 | |
| Letter discussing sourcing materials for a 'Goshawk' Ignition Condenser. | 28th Nov 1921 | Box 52 \ 3 Scan024 | |
| Telegram confirmation to EFC regarding the sourcing and alteration of a paper condenser. | 28th Nov 1921 | Box 52 \ 3 Scan025 | |
| Confirmation of a telegram to EFC regarding the rearrangement of an ignition tower and folded paper condenser. | 28th Nov 1921 | Box 52 \ 3 Scan026 | |
| Experimental memorandum detailing drawings and parts for an alternative 'Goshawk' 11 Condenser design. | 11th Feb 1921 | Box 52 \ 3 Scan027 | |
| Confirmation of a telegram regarding a condenser problem dependent on procuring specific paper. | 29th Nov 1921 | Box 52 \ 3 Scan028 | |
| Specification sheet for paper to be used in rolled condensers. | 29th Nov 1921 | Box 52 \ 3 Scan029 | |
| Requesting a supply of thin oiled condenser paper for making battery ignition coils. | 30th Nov 1921 | Box 52 \ 3 Scan030 | |
| Dispatch of an advance blueprint for the Goshawk Condenser. | 1st Dec 1921 | Box 52 \ 3 Scan031 | |
| Progress report on the development of mica and paper condensers for the 'Goshawk' ignition system. | 1st Dec 1921 | Box 52 \ 3 Scan032 | |
| Suitable varnishes and impregnated paper for building mica condensers. | 1st Dec 1921 | Box 52 \ 3 Scan033 | |
| Specification for condenser paper to suit an arrangement where it is folded flat and placed vertically on the side of an ignition tower. | 2nd Dec 1921 | Box 52 \ 3 Scan034 | |
| The production and testing of Goshawk condensers using a newly discovered insulating paper. | 2nd Dec 1921 | Box 52 \ 3 Scan035 | |
| The development and comparative trial of condensers for the 'Goshawk' ignition system using oiled paper and tin foil. | 6th Dec 1921 | Box 52 \ 3 Scan036 | |
| Use of aluminium foil and oiled silk as materials for condensers. | 16th Dec 1921 | Box 52 \ 3 Scan037 | |
| Request for materials including paper, silk dielectric, and foil for experimental work on the Goshawk condenser. | 6th Dec 1921 | Box 52 \ 3 Scan038 | |
| Specification detailing the materials and construction for a double interleaved strip for a rolled condenser. | 12th Dec 1921 | Box 52 \ 3 Scan039 | |
| Copy of a letter from The L.P.S. Electrical Co. regarding an enquiry for insulating strip. | 8th Dec 1921 | Box 52 \ 3 Scan040 | |
| Quotation letter from L.P.S. Electrical Company detailing prices and delivery times for insulating varnished paper and silk. | 26th Nov 1923 | Box 52 \ 3 Scan041 | |
| Improvements to the R.R. Goshawk Condenser, including capacity and material considerations. | 9th Dec 1921 | Box 52 \ 3 Scan042 | |
| Materials and construction methods for electrical components, specifically dielectrics and winding. | 12th Sep 1921 | Box 52 \ 3 Scan043 | |
| Letter from The British Lighting and Ignition Co. Ltd. regarding the disposal of Tin-foil. | 12th Dec 1921 | Box 52 \ 3 Scan044 | |
| Ordering materials, like paper or silk dielectric, for a Goshawk condenser. | 14th Dec 1921 | Box 52 \ 3 Scan045 | |
| Page 2 of a memo stating Mr. Royce's opinion on obtaining four thicknesses of material ready interleaved. | 14th Dec 1921 | Box 52 \ 3 Scan046 | |
| Revised widths for foils and paper in the Goshawk engine condenser. | 17th Dec 1921 | Box 52 \ 3 Scan047 | |
| Letter from an insulation specialist discussing the use of tin-foil versus aluminium foil with varnished silk. | 17th Dec 1931 | Box 52 \ 3 Scan048 | |
| Required thickness of paper or silk dielectric material for a Goshawk condenser. | 29th Dec 1921 | Box 52 \ 3 Scan049 | |
| Battery ignition condenser capacity for the 40/50 and Goshawk engines. | 29th Dec 1921 | Box 52 \ 3 Scan050 | |
| Continued discussion on ignition phenomena, focusing on condenser discharge and contact effects in the Goshawk ignition system. | 3rd Jan 1922 | Box 52 \ 3 Scan051 | |
| Letter from H.D. Symons & Co. Ltd. detailing experiments with insulated aluminium foil for condenser work. | 3rd Jan 1922 | Box 52 \ 3 Scan052 | |
| Page two of a letter from H.D. Symons & Co. Ltd. discussing the properties of varnished silk and aluminium foil samples. | 3rd Jan 1922 | Box 52 \ 3 Scan053 | |
| Receipt of oiled silk strip from the Ioco Co. for experimental Goshawk condensers. | 4th Jan 1922 | Box 52 \ 3 Scan054 | |
| Experimental instructions and bill of materials for the Goshawk 11 Condenser. | 11th Jan 1922 | Box 52 \ 3 Scan055 | |
| Note on the winding of a Condenser Roll onto a .850 diameter bobbin for ease of manufacture. | 15th Mar 1917 | Box 52 \ 3 Scan056 | |
| Letter from Wraptyn Co. Limited regarding samples and an order of Pure Tinfoil. | 12th Jan 1922 | Box 52 \ 3 Scan057 | |
| Confirming and detailing the materials being obtained for a Goshawk condenser. | 23th Jan 1922 | Box 52 \ 3 Scan058 | |
| Letter from H.D. Symons & Co. regarding unsatisfactory varnished silk aluminium foil samples and proposals for alternatives. | 14th Jan 1922 | Box 52 \ 3 Scan059 | |
| Telegram received by telephone confirming a cable about condensor strip works was posted from New York. | 8th Feb 1943 | Box 52 \ 3 Scan060 | |
| Inquiry about obtaining a thinner silk dielectric for Goshawk ignition condensers from the Ioco Company. | 16th Feb 1922 | Box 52 \ 3 Scan061 | |
| Confirming the satisfactory quality of oiled paper for the Goshawk Condenser and requesting an order for 100 sets. | 23th Feb 1922 | Box 52 \ 3 Scan062 | |
| Technical update on the development and specifications of the Goshawk Ignition system components. | 24th Feb 1922 | Box 52 \ 3 Scan063 | |
| Goshawk engine condenser capacity tests, observing misfiring speeds under different conditions. | 16th Mar 1922 | Box 52 \ 3 Scan064 | |
| Capacity limits for Goshawk battery ignition condensers and requesting samples for testing. | 20th Jul 1922 | Box 52 \ 3 Scan065 | |
| Log sheet detailing test results for experimental condensers. | 27th Jul 1922 | Box 52 \ 3 Scan066 | |
| Log sheet detailing materials, tests, and outcomes for numbered components. | 15th Mar 1922 | Box 52 \ 3 Scan067 | |
| Graph showing curves of spark-lengths and current consumptions for Coils G.B.S. and S.B.I. | 21th Dec 1932 | Box 52 \ 3 Scan068 | |
| Internal instruction sheet regarding the acceptance of Goshawk II condensers for testing. | 10th Aug 1922 | Box 52 \ 3 Scan069 | |
| The production test specification for the Goshawk ignition condenser. | 25th Aug 1922 | Box 52 \ 3 Scan070 | |
| Production test procedure for a paper dielectric condenser for Goshawk battery ignition. | 25th Aug 1922 | Box 52 \ 3 Scan071 | |
| Testing procedures and specifications for a condenser, including charge holding, capacity, and sparking tests. | 25th Oct 1922 | Box 52 \ 3 Scan072 | |
| Tests and proposed modifications for the Goshawk ignition system's condenser connections. | 25th Oct 1922 | Box 52 \ 3 Scan073 | |
| Page detailing modifications to condensers for four Goshawk demonstration cars. | 27th Oct 1922 | Box 52 \ 3 Scan074 | |
| Modifications to the 'GOSHAWK II' Condenser and their unsuitability for production. | 27th Oct 1922 | Box 52 \ 3 Scan075 | |
| The acceptable foil thickness for the Goshawk condenser. | 2nd Mar 1923 | Box 52 \ 3 Scan076 | |
| The failure of a Goshawk ignition condenser, referencing a previously ignored design recommendation. | 15th May 1923 | Box 52 \ 3 Scan077 | |
| Condenser failures, attributing them to production issues and proposing solutions including an update to the production test specification. | 5th May 1923 | Box 52 \ 3 Scan078 | |
| Investigation into a faulty condenser, number 320. | 14th May 1923 | Box 52 \ 3 Scan079 | |
| Page two of an inspection report on a faulty condenser, detailing observed defects and suggesting new production tests. | 16th May 1923 | Box 52 \ 3 Scan080 | |
| Test report for condenser No. 2, detailing leakage and capacity checks. | 16th May 1923 | Box 52 \ 3 Scan081 | |
| Trouble with the Goshawk ignition condensor, specifically points burning and pitting. | 23th May 1923 | Box 52 \ 3 Scan082 | |
| Design improvement and testing of Goshawk condensers. | 8th Mar 1923 | Box 52 \ 3 Scan083 | |
| Test report for Condenser No. 494 with improved connections. | 31th May 1923 | Box 52 \ 3 Scan084 | |
| Design issues and failures of the Goshawk ignition condenser connections due to high-frequency currents. | 28th May 1923 | Box 52 \ 3 Scan085 | |
| Improving the design of a condenser's metallic connection using presspan. | 28th May 1923 | Box 52 \ 3 Scan086 | |
| Test report on the effect of temperature on a Goshawk rolled paper condenser. | 11th Jun 1923 | Box 52 \ 3 Scan087 | |
| Instruction sheet detailing the checking of readings for rising and falling temperature curves. | 6th Nov 1918 | Box 52 \ 3 Scan088 | |
| Proposing a test for electrical contacts in high-frequency circuits, such as ignition and radio systems. | 11th Jun 1923 | Box 52 \ 3 Scan089 | |
| | | | |
