| Description | Date | Identifier | |
| Letter to The Adamant Engineering Co. regarding the specifications and testing of a new steering cam. | 2nd Nov 1934 | Box 28 \ 3 Scan036 | |
| Letter from Adamant Engineering Company acknowledging receipt of a letter and awaiting a gear. | 3rd Nov 1934 | Box 28 \ 3 Scan037 | |
| Letter from Adamant Engineering Company regarding a meeting to discuss a change in steering gear ratio. | 7th Nov 1934 | Box 28 \ 3 Scan038 | |
| Letter to Adamant Engineering Co. Ltd. arranging a meeting to discuss altering a steering ratio and the manufacture of Marles steering. | 6th Nov 1934 | Box 28 \ 3 Scan039 | |
| General arrangement of a Marles Steering Gear, RH 1 7/8 type. | 16th Mar 1934 | Box 28 \ 3 Scan040 | |
| Letter from The Rover Company Ltd regarding steering gear particulars. | 10th Nov 1934 | Box 28 \ 3 Scan041 | |
| Letter from Burman & Sons Ltd. regarding the technical particulars of the Burman-Douglas Steering Gear. | 9th Nov 1934 | Box 28 \ 3 Scan042 | |
| Manual for the Burman Douglas Steering Gear. | 10th Nov 1934 | Box 28 \ 3 Scan043 | |
| The reversal rig test of a Marles Steering Column Ex.16005. | 10th Nov 1934 | Box 28 \ 3 Scan044 | |
| Arrangement drawing for a Rover 1 inch steering gear. | 15th Oct 1934 | Box 28 \ 3 Scan045 | |
| Letter to Messrs. Burman & Sons Ltd. requesting further details about their steering gear, specifically its efficiency and helix angle. | 12th Nov 1934 | Box 28 \ 3 Scan046 | |
| Letter to The Rover Co. Ltd. regarding details of Burman-Douglas steering. | 12th Nov 1934 | Box 28 \ 3 Scan047 | |
| Letter to The Adamant Engineering Co. Ltd. regarding the testing and efficiency of a Marles type L.7 steering gear on a 25 HP chassis. | 13th Nov 1934 | Box 28 \ 3 Scan048 | |
| Letter from Adamant Engineering Company discussing the gear ratio and efficiency of the L7 Gear for Marles-Weller steering gears. | 14th Nov 1934 | Box 28 \ 3 Scan049 | |
| Letter from Adamant Engineering discussing steering gear ratios and helix angles. | 14th Nov 1934 | Box 28 \ 3 Scan050 | |
| The modification of a Marles Type L.7 Steering Gear by the Adamant Engineering Co. | 14th Nov 1934 | Box 28 \ 3 Scan051 | |
| Request to manufacture a new, shorter pendulum lever for the Marles Steering Gear on Chassis 21-G-IV. | 15th Nov 1934 | Box 28 \ 3 Scan052 | |
| Research into Marles steering for the Spectre project, comparing it with La Salle steering. | 16th Nov 1934 | Box 28 \ 3 Scan053 | |
| Comparing steering gear efficiency, discussing component manufacturing, and proposing tests for the Spectre model. | 16th Nov 1934 | Box 28 \ 3 Scan054 | |
| The mechanical efficiency of a Marles Type L.7 Steering Gear for 25 HP. | 15th Nov 1934 | Box 28 \ 3 Scan055 | |
| The mechanical efficiency tests of the Marles Type L.7 steering gear on chassis 21-G-IV. | 18th Nov 1934 | Box 28 \ 3 Scan056 | |
| The necessity of a long pendulum lever for the Marles type steering gear. | 15th Nov 1934 | Box 28 \ 3 Scan057 | |
| Calculations for the approximate helix angle of 'La Salle' and 'Marles Type L.7' steering gears. | 15th Nov 1934 | Box 28 \ 3 Scan058 | |
| Blank page with a 'PRINT ROOM' stamp from Derby. | 15th Nov 1934 | Box 28 \ 3 Scan059 | |
| Graph showing the mechanical efficiency of a La Salle steering system against load. | 16th Nov 1934 | Box 28 \ 3 Scan060 | |
| Blank page with a purple stamp from the Print Room in Derby. | 16th Nov 1934 | Box 28 \ 3 Scan061 | |
| Graph showing the mechanical efficiency of a Marles Type L.7 steering gear. | 13th Nov 1934 | Box 28 \ 3 Scan062 | |
| Cover or backing sheet stamped by the Print Room. | 15th Nov 1934 | Box 28 \ 3 Scan063 | |
| Comparison of the outlines of Marles Type L.7 and Gemmer Model 330 steering gears. | 18th Nov 1924 | Box 28 \ 3 Scan064 | |
| Blueprint of a left-hand steering assembly with a ratio of 20.25 to 1. | 1st May 1939 | Box 28 \ 3 Scan065 | |
| Letter from Burman & Sons Ltd. discussing the specifications of a Burman-Douglas steering gear. | 14th Nov 1934 | Box 28 \ 3 Scan066 | |
| Letter from Burman & Sons, Ltd. regarding comparative gear efficiency. | 14th Dec 1934 | Box 28 \ 3 Scan067 | |
| Internal request to place an order with Adamant Engineering Co. for a modified experimental steering gear. | 16th Nov 1934 | Box 28 \ 3 Scan068 | |
| Letter to Adamant Engineering Co. Ltd. detailing the specifications for a new Type L.7 R.H. steering gear for a 25 HP chassis. | 16th Nov 1934 | Box 28 \ 3 Scan069 | |
| Letter discussing the use of a special oil for testing and running in an L.7 gear. | 19th Nov 1934 | Box 28 \ 3 Scan070 | |
| Letter from Adamant Engineering Company regarding the production of an L7 Gear, a drop arm, and gear oil. | 19th Nov 1934 | Box 28 \ 3 Scan071 | |
| Page two of a letter from Adamant Engineering Company Limited. | 19th Nov 1934 | Box 28 \ 3 Scan072 | |
| Letter to Cadillac Motor Car Co. inquiring about the advantages of American-style steering gears. | 19th Nov 1934 | Box 28 \ 3 Scan073 | |
| Capacity of a Saginaw steering gear and requesting specifications for Cadillac and La Salle steering cams. | 19th Nov 1934 | Box 28 \ 3 Scan074 | |
| Ordering and fitting of a Marles Steering Gear and the fabrication of pendulum levers for chassis GUB-V. | 19th Nov 1934 | Box 28 \ 3 Scan075 | |
| Helix angle of Cadillac steering and comparing its shock immunity to La Salle steering. | 22th Nov 1934 | Box 28 \ 3 Scan076 | |
| Urgent request via telegram to Adamant in Luton for a second L.7 gear. | 28th Nov 1934 | Box 28 \ 3 Scan077 | |
| Telegram received by telephone regarding the dispatch of a 'second LY gear'. | 28th Nov 1934 | Box 28 \ 3 Scan078 | |
| Development of the Spectre steering system, referencing Cadillac and La Salle steering. | 3rd Dec 1934 | Box 28 \ 3 Scan079 | |
| Comparison table of data for various types of 25 HP steering gear. | 7th Jan 1935 | Box 28 \ 3 Scan080 | |
| Comparison table of specifications for various types of steering gear. | 7th Jan 1935 | Box 28 \ 3 Scan081 | |
| Mechanical efficiency test results for a Marles Weller Q Type Steering Gear. | 11th Dec 1934 | Box 28 \ 3 Scan082 | |
| Note on the efficiency of steering gears and the time taken for an oil film to squash out under load. | 11th Dec 1934 | Box 28 \ 3 Scan083 | |
| Modifications for the Spectre Marles type steering column and a related clearance issue. | 14th Dec 1934 | Box 28 \ 3 Scan084 | |
| Follow-up letter to Adamant Engineering Co. Ltd. regarding the progress on a double tooth type steering for a Bentley and a new large hourglass worm steering gear. | 31th Dec 1934 | Box 28 \ 3 Scan085 | |
| Letter from Adamant Engineering Company acknowledging a letter concerning steerings. | 4th Jan 1935 | Box 28 \ 3 Scan086 | |
| Despatch of a Pendulum Lever to the Adamant Engineering Co. for splining. | 1st Jan 1935 | Box 28 \ 3 Scan087 | |
| Data table comparing different types of 25 HP steering gear. | 7th Jan 1935 | Box 28 \ 3 Scan088 | |
| Comparison table of specifications for different types of steering gear. | 7th Jan 1935 | Box 28 \ 3 Scan089 | |
| Request to fit a side steering tube with limited movement and increased set up load on Wor's car. | 18th Jan 1935 | Box 28 \ 3 Scan090 | |
| The lower ratio Marles type steering on Wor's car. | 2nd Feb 1935 | Box 28 \ 3 Scan091 | |
| Letter to The Adamant Engineering Co. Ltd. regarding the modification of a steering part. | 4th Feb 1935 | Box 28 \ 3 Scan092 | |
| Letter from Adamant Engineering Company regarding arrangements for gear parts. | 5th Feb 1935 | Box 28 \ 3 Scan093 | |
| Letter to Adamant Engineering Co. Ltd. confirming arrangements for steering parts. | 6th Feb 1935 | Box 28 \ 3 Scan094 | |
| Taking a steering gear from car 21-G-IV to the Marles Company to have the ratio changed. | 7th Feb 1935 | Box 28 \ 3 Scan095 | |
| Letter from Adamant Engineering Company regarding the supply of Cams and Rollers for order 75967, and a note on a centre bore issue. | 8th Feb 1935 | Box 28 \ 3 Scan096 | |
| Letter from Adamant Engineering Company confirming a meeting with Mr. Robotham. | 7th Feb 1935 | Box 28 \ 3 Scan097 | |
| Copy of a telegram confirming despatch of parts for order 75967. | 7th Feb 1935 | Box 28 \ 3 Scan098 | |
| Letter to The Adamant Engineering Co. Ltd. outlining decisions on a double tooth gear for a Bentley. | 11th Feb 1935 | Box 28 \ 3 Scan099 | |
| Typed letter clarifying specifications for a steering gear part and confirming an upcoming order. | 11th Feb 1935 | Box 28 \ 3 Scan100 | |
| Request to pass an official order to The Adamant Engineering Co. Ltd. for a Double Tooth Steering Gear for a Bentley. | 12th Feb 1935 | Box 28 \ 3 Scan101 | |
| The requirements for fitting a Marles steering gear to a Bentley chassis. | 12th Feb 1935 | Box 28 \ 3 Scan102 | |
| Modifications required for Marles and Peregrine steering tubes. | 12th Feb 1935 | Box 28 \ 3 Scan103 | |
| Letter from Adamant Engineering Company regarding L7 Gears, related drawings, and an upcoming meeting. | 16th Feb 1935 | Box 28 \ 3 Scan104 | |
| Letter from Adamant Engineering Company confirming an appointment to discuss L.7 Steering parts. | 15th Feb 1935 | Box 28 \ 3 Scan105 | |
| Letter from Adamant Engineering Company regarding specifications and arrangements for a steering gear order. | 12th Feb 1935 | Box 28 \ 3 Scan106 | |
| Letter from Adamant Engineering Company Limited concerning 3 special Cams and Rollers they supplied. | 12th Feb 1935 | Box 28 \ 3 Scan107 | |
| Letter to Adamant Engineering Co. Ltd. requesting an L.7 type Steering Gear for examination and potential standardisation on the 25 HP chassis. | 15th Feb 1935 | Box 28 \ 3 Scan108 | |
| Letter requesting the production of a third L.7 type R.H. Gear with four specific modifications. | 15th Feb 1935 | Box 28 \ 3 Scan109 | |
| Requesting an official order be sent for L.7 type R.H. Steering Gear for Sg's car. | 15th Feb 1935 | Box 28 \ 3 Scan110 | |
| Requesting the fitment of a Marles L.7 steering gear to a 25 HP car, chassis GLG-5, with modification details. | 15th Feb 1935 | Box 28 \ 3 Scan111 | |
| Letter to Adamant Engineering concerning the standardisation and modification of L.7 type steering gear for a 25 HP chassis. | 15th Feb 1935 | Box 28 \ 3 Scan112 | |
| Page 2 of a letter detailing requirements for an improvised oil filler and column projection. | 15th Feb 1935 | Box 28 \ 3 Scan113 | |
| Experimental fitting and proposed standardisation of Marles steering gear on a 25 HP model. | 16th Feb 1935 | Box 28 \ 3 Scan114 | |
| General arrangement of Marles Steering Gear L7 Type RH. | 24th Apr 1930 | Box 28 \ 3 Scan115 | |
| General arrangement of Marles Steering Gear, L.7. Type R.H. | 3rd Jul 1934 | Box 28 \ 3 Scan116 | |
| Standardising the Marles steering on the 20/25 chassis. | 15th Feb 1935 | Box 28 \ 3 Scan117 | |
| Comparison and proposal for standardizing Marles steering on the 20/25 model. | 20th Feb 1935 | Box 28 \ 3 Scan118 | |
| Comparison of a standard steering column with a proposed Marles column, detailing design, materials, and weight. | 20th Feb 1935 | Box 28 \ 3 Scan119 | |
| Comparison table of specifications for two different steering gear systems, the Standard 20/25 and the 20/25 Marles. | 21th Feb 1935 | Box 28 \ 3 Scan120 | |
| Disappointing mechanical efficiency results of the Marles steering gear on the 21-G-IV chassis. | 21th Feb 1935 | Box 28 \ 3 Scan121 | |
| Graph showing the mechanical efficiency of a Marles Type L7 steering gear under forward and reverse drive. | 27th Feb 1935 | Box 28 \ 3 Scan122 | |
| Blank document page with a purple ink stamp from the Print Room in Derby. | 28th Feb 1935 | Box 28 \ 3 Scan123 | |
| Graph showing the mechanical efficiency of a Marles Type L.T steering gear after a 7-hour test run. | 13th Nov 1934 | Box 28 \ 3 Scan124 | |
| Graph showing the mechanical efficiency of a Marles Type L7 steering column under different loads. | 12th Oct 1934 | Box 28 \ 3 Scan125 | |
| Updating the outside diameter dimension for the Double Tooth Marles Steering box cover on a Bentley chassis. | 21th Feb 1935 | Box 28 \ 3 Scan126 | |
| Mechanical efficiency of the Marles steering gear on the 21-G-IV model. | 21th Feb 1935 | Box 28 \ 3 Scan127 | |
| Letter to Adamant Engineering Co. Ltd. requesting a detail print for a steering gear top cover part M.20718 for a Bentley. | 28th Feb 1935 | Box 28 \ 3 Scan128 | |
| Invoice received from Adamant Engineering Co. Ltd. for steering gear components. | 1st Mar 1935 | Box 28 \ 3 Scan129 | |
| Letter from Adamant Engineering Company, Limited regarding blueprints M.20718 and MGA.20620B for a special Top Cover and gear assembly. | 1st Mar 1935 | Box 28 \ 3 Scan130 | |
| Modifications to the Marles type steering for the 20/25 HP chassis, intended for Adamant Engineering Co. | 4th Mar 1935 | Box 28 \ 3 Scan131 | |
| Stop-work order concerning alterations to Marles type steering parts for the 20/25 HP Chassis. | 6th Mar 1935 | Box 28 \ 3 Scan132 | |
| Authorising payment for an invoice from the Adamant Engineering Co. | 8th Mar 1935 | Box 28 \ 3 Scan133 | |
| Note concerning letters and booklets for Marles Steering Gear received from Adamant Engineering Co. Ltd. | 9th Mar 1935 | Box 28 \ 3 Scan134 | |
| Letter from Adamant Engineering Company regarding the supply and distribution of instruction booklets for steering gears. | 7th Mar 1935 | Box 28 \ 3 Scan135 | |
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