| Description | Date | Identifier | |
| Table of dynamometer ratios for Humber, Dodge, and Hupmobile cars at different RPMs. | 3rd May 1921 | Box 126 \ 2 scan0018 | |
| The registration status of a Humber car. | 3rd May 1921 | Box 126 \ 2 scan0019 | |
| Follow-up request regarding the registration book for the Humber Car. | 5th Jul 1921 | Box 126 \ 2 scan0020 | |
| Request for the registration book of a Humber car. | 1st Jul 1921 | Box 126 \ 2 scan0021 | |
| Request for a speedometer drive for a 15.9HP Humber car. | 11th Aug 1921 | Box 126 \ 2 scan0022 | |
| The despatch of a speedometer drive to Conduit Street. | 16th Aug 1921 | Box 126 \ 2 scan0023 | |
| Official order to instruct Messrs. Holmes Bros. to carry out work on a Humber car for the sum of £1. 5. 0. | 20th Sep 1921 | Box 126 \ 2 scan0024 | |
| Specification memo for 'SWALLOW' discussing the merits of 4-cylinder versus 6-cylinder engines for a small horsepower car. | 10th Jan 1922 | Box 126 \ 2 scan0025 | |
| Stating the total mileage of a Humber Car. | 13th Mar 1931 | Box 126 \ 2 scan0026 | |
| Cover letter for a criticism report on a 16/50 Humber car. | 13th Mar 1931 | Box 126 \ 2 scan0027 | |
| Technical report on the performance of a 16/50 Humber car. | 13th Mar 1931 | Box 126 \ 2 scan0028 | |
| The accuracy of a speedometer at various speeds. | 2nd Jun 1931 | Box 126 \ 2 scan0029 | |
| Road test report comparing the performance of a Humber Snipe Fabric saloon with a Rolls-Royce 20/25 HP. | 2nd Jun 1931 | Box 126 \ 2 scan0030 | |
| Technical evaluation report on a car's performance, focusing on the engine, handling, and braking. | 2nd Jun 1931 | Box 126 \ 2 scan0031 | |
| Letter to The Humber Motor Co. Ltd. regarding difficulties with valve springs, inquiring about material specifications to determine if the issue is with the design or faulty material. | 15th Jun 1936 | Box 126 \ 2 scan0032 | |
| Letter from Humber Ltd. concerning a discussion about Valve Spring trouble. | 16th Jun 1936 | Box 126 \ 2 scan0033 | |
| Letter from Humber Ltd. inquiring about engine timing diagrams and carburation difficulties. | 11th Jul 1936 | Box 126 \ 2 scan0034 | |
| Letter to Humber Ltd. discussing engine idling issues related to valve overlap and tappet clearance. | 13th Jul 1936 | Box 126 \ 2 scan0035 | |
| The concluding page of a letter apologising for the lack of conciseness due to the subject's complexity. | 13th Jul 1936 | Box 126 \ 2 scan0036 | |
| Letter from Humber Limited to W.A. Rowbotham discussing an idling problem. | 14th Jul 1936 | Box 126 \ 2 scan0037 | |
| Letter from Humber Ltd. to W.A. Rowbotham concerning research into breaking valve springs. | 30th Jun 1936 | Box 126 \ 2 scan0038 | |
| Valve spring failures in various engines from 1935 and 1936. | 30th Jun 1936 | Box 126 \ 2 scan0039 | |
| Spring failures due to wire defects and torsion fatigue, detailing the specifications for 'Aero quality wire' and a new double telescopic spring design. | 19th Jun 1935 | Box 126 \ 2 scan0040 | |
| Blueprint specifications for a Valve Spring for a Cylinder Block. | 19th Jun 1935 | Box 126 \ 2 scan0041 | |
| Design drawing for a valve spring for a cylinder block. | 20th Jun 1935 | Box 126 \ 2 scan0042 | |
| Engineering drawing for an inner valve spring for a Humber Hillman 6 cylinder engine. | 26th Jun 1936 | Box 126 \ 2 scan0043 | |
| Blueprint for an outer valve spring for an engine. | 26th Jun 1938 | Box 126 \ 2 scan0044 | |
| Drawing and specifications for a valve spring for a cylinder block. | 30th Aug 1936 | Box 126 \ 2 scan0045 | |
| Blueprint for an engine cylinder head outer inlet valve spring. | 27th Jun 1930 | Box 126 \ 2 scan0046 | |
| Drawing of an inlet valve spring (inner) for an engine cylinder head. | 27th Jun 1938 | Box 126 \ 2 scan0047 | |
| Graph plotting various alphanumeric codes as vertical line segments between two diagonal lines. | 4th Aug 1936 | Box 126 \ 2 scan0048 | |
| Letter to Messrs. Humber Ltd. discussing the use of Chrome-Vanadium for valve springs and design considerations. | 4th Aug 1936 | Box 126 \ 2 scan0049 | |
| Letter to Mr. Rootes of Humber Ltd. arranging a meeting to discuss frames and road springs. | 28th Jan 1937 | Box 126 \ 2 scan0050 | |
| Letter from Humber Ltd. regarding the arrangement of a meeting to discuss frames and road springs, with handwritten notes. | 30th Jan 1937 | Box 126 \ 2 scan0051 | |
| Short internal memo regarding a visit to the Humber Factory. | 2nd Feb 1937 | Box 126 \ 2 scan0052 | |
| Letter to B.B. Winter of Humber Ltd. confirming an arranged meeting. | 9th Feb 1937 | Box 126 \ 2 scan0053 | |
| Letter from Humber Ltd. requesting to inspect a mechanical Servo for research purposes. | 28th Jul 1937 | Box 126 \ 2 scan0054 | |
| Letter to Mr. Winter of Humber Ltd. arranging a visit for their Transmission Engineer to see a Servo. | 30th Jul 1937 | Box 126 \ 2 scan0055 | |
| Letter from Humber Ltd. arranging a visit for their Transmission Engineer to inspect a Servo at the Rolls-Royce Works. | 5th Aug 1937 | Box 126 \ 2 scan0056 | |
| Letter to Humber Ltd. regarding a demonstration of the quietness of their un-ground gearbox gears. | 2nd Sep 1937 | Box 126 \ 2 scan0057 | |
| Letter from Humber Limited to S.H. Grylls of Rolls-Royce confirming arrangements for trial runs on cars with unground teeth on the gears. | 3rd Sep 1937 | Box 126 \ 2 scan0058 | |
| Letter of thanks to Mr. R.C. Hughes of Humber Limited following a visit. | 15th Sep 1937 | Box 126 \ 2 scan0059 | |
| Letter from Humber Ltd. acknowledging a letter regarding service for Mr. Burns' car gearbox. | 23th Sep 1937 | Box 126 \ 2 scan0060 | |
| Letter to Humber Ltd. requesting chassis weight information for the 'Snipe' Sports Saloon. | 6th Aug 1938 | Box 126 \ 2 scan0061 | |
| Review of the Humber 'Snipe' and requesting a seating accommodation comparison with a B.III model. | 8th Aug 1938 | Box 126 \ 2 scan0062 | |
| Letter from Humber Limited detailing the construction and weight of the Snipe Sports Saloon. | 8th Aug 1938 | Box 126 \ 2 scan0063 | |
| Comparing dimensions and weight of a Humber Snipe Saloon and a B.III (PD.206) vehicle. | 12th Aug 1938 | Box 126 \ 2 scan0064 | |
| Continued comparison of two car models focusing on interior space, wheelbase, and track width. | 12th Aug 1938 | Box 126 \ 2 scan0065 | |
| Calculating and comparing the chassis and body weights of a Humber Snipe Sports Saloon. | 13th Aug 1938 | Box 126 \ 2 scan0066 | |
| Weight comparison table and analysis for the Snipe Sports Saloon and 7.B.5. models. | 13th Aug 1938 | Box 126 \ 2 scan0067 | |
| Enquiry to Humber Ltd. about patents for a wheel arrangement and a request for speedometer gears. | 14th Sep 1938 | Box 126 \ 2 scan0068 | |
| Letter from Humber Limited regarding patent inquiries for wheel discs, also mentioning Cornercroft and Talbot. | 16th Sep 1938 | Box 126 \ 2 scan0069 | |
| Letter to Humber Limited recommending an aluminium tin alloy bearing for high-performance engines. | 2nd Dec 1938 | Box 126 \ 2 scan0070 | |
| Letter from Humber Limited acknowledging receipt of correspondence from W.A. Robotham. | 5th Dec 1938 | Box 126 \ 2 scan0071 | |
| Letter from Humber Ltd. discussing the Super Snipe car and their engine bearing technology. | 6th Dec 1938 | Box 126 \ 2 scan0072 | |
| Letter to B.B. Winter of Humber Ltd. regarding Babbitt-lined main bearings and a request to test a 'Super Snipe'. | 8th Dec 1938 | Box 126 \ 2 scan0073 | |
| Letter from Humber Limited acknowledging receipt of a letter from W.A. Robotham. | 9th Dec 1938 | Box 126 \ 2 scan0074 | |
| Copy of a letter from Humber Ltd. providing a reference for the Pattern Model Co. | 10th Dec 1938 | Box 126 \ 2 scan0075 | |
| Quotation from The Pattern & Model Co, Ltd. for cylinder patterns and coreboxes. | 10th Dec 1938 | Box 126 \ 2 scan0076 | |
| Letter from Humber Ltd. to W.A. Robotham regarding a test drive of a Super Snipe demonstrator car. | 13th Dec 1938 | Box 126 \ 2 scan0077 | |
| Letter to W.W. Winter of Humber Ltd. arranging a trial of the 'Super Snipe' car. | 19th Dec 1938 | Box 126 \ 2 scan0078 | |
| Letter from Humber Ltd. to W.A. Robotham arranging to send a Super Snipe vehicle for review. | 22th Dec 1938 | Box 126 \ 2 scan0079 | |
| Letter to B.B. Winter of Humber Ltd. arranging a visit to discuss motor-cars, gearboxes, the 'Super Snipe', and a 'Wraith'. | 29th Dec 1938 | Box 126 \ 2 scan0080 | |
| Letter from Humber Ltd. confirming a meeting to discuss business and try the Wraith. | 30th Dec 1938 | Box 126 \ 2 scan0081 | |
| B.50 gearbox issue where 2nd speed comes out of mesh, proposing an experimental fix. | 13th Jan 1939 | Box 126 \ 2 scan0082 | |
| The telephone order of an exhaust system for a Humber Super 'Snipe' from Pickfords. | 16th Jan 1939 | Box 126 \ 2 scan0083 | |
| Letter to Messrs. Humber Ltd. about a method for correcting gears that jump out on the overrun. | 21th Jan 1939 | Box 126 \ 2 scan0084 | |
| Letter from Humber Limited to S.H.Grylls discussing solutions for gearbox gear jumping issues. | 24th Jan 1939 | Box 126 \ 2 scan0085 | |
| Letter from Humber Limited discussing methods for overcoming gearbox troubles, specifically the issue of gears jumping out. | 24th Jan 1939 | Box 126 \ 2 scan0086 | |
| And diagrams illustrating the design and behavior of a 1st speed gear, including the effects of the quenching method. | 26th Aug 1938 | Box 126 \ 2 scan0087 | |
| Technical drawing of a 1st speed synchro unit assembly, showing components, assembly instructions, and modifications. | 26th Aug 1938 | Box 126 \ 2 scan0088 | |
| Letter to Humber Ltd. requesting assistance in manufacturing a new experimental reverse gear. | 26th Jan 1939 | Box 126 \ 2 scan0089 | |
| Letter from Humber Limited discussing two methods and costs for a specific machining job. | 27th Jan 1939 | Box 126 \ 2 scan0090 | |
| Letter from Humber Ltd. discussing a job and asking how to finish gear teeth after hardening. | 27th Jan 1939 | Box 126 \ 2 scan0091 | |
| Evaluation of competitor cars, a Jaguar and a Humber Super Snipe, and proposing a part exchange. | 31th Jan 1939 | Box 126 \ 2 scan0092 | |
| Acquisition of a Humber Super Snipe for the Experimental Department, potentially by exchanging a Jaguar. | 21th Jan 1939 | Box 126 \ 2 scan0093 | |
| Quotation from an automobile distributor for the part-exchange of a Humber for a Jaguar. | 2nd Feb 1939 | Box 126 \ 2 scan0094 | |
| Letter to R.C. Hughes of Humber Ltd. requesting an opinion on the De Normanville overdrive. | 4th Feb 1939 | Box 126 \ 2 scan0095 | |
| Official order for a Humber Super Snipe Saloon and confirming the swap of a Jaguar. | 7th Feb 1939 | Box 126 \ 2 scan0096 | |
| Letter to Humber Ltd. thanking them for the loan of a car which resulted in the purchase of a 'Super Snipe'. | 21th Feb 1939 | Box 126 \ 2 scan0097 | |
| Invoice from E.H. Pickford & Co. Ltd for a Humber Super Snipe Saloon with a part-exchange for an S.S. Jaguar. | 24th Feb 1939 | Box 126 \ 2 scan0098 | |
| Confirming that extra charges related to the purchase of a Humber Snipe are in order. | 27th Feb 1939 | Box 126 \ 2 scan0099 | |
| The disposal of an S.S. Jaguar and the purchase of a Humber Super Snipe Saloon. | 27th Feb 1939 | Box 126 \ 2 scan0100 | |
| Confirming the receipt of a Humber Super Snipe car from Messrs. Pickfords, including licensing and number plates. | 1st Mar 1939 | Box 126 \ 2 scan0101 | |
| Sending of 1/10th scale drawings for the 'Century Buick' Series 60 and the Humber Super-Snipe Saloon. | 11th Mar 1939 | Box 126 \ 2 scan0102 | |
| Modification to a selector guide shaft to prevent oil leaks using a split felt ring. | 27th Mar 1939 | Box 126 \ 2 scan0103 | |
| Layout of the front end of a car for the bonnet and dashboard pressing for a Wraith 80 model. | 27th Mar 1939 | Box 126 \ 2 scan0104 | |
| Technical memo detailing the windage and performance data for a 1939 Humber Super Snipe. | 17th Mar 1939 | Box 126 \ 2 scan0105 | |
| Dynamometer test graph showing BHP at road wheels for a 1939 Humber Super Snipe. | 15th Mar 1939 | Box 126 \ 2 scan0106 | |
| Requesting a test drive of a Humber Snipe car. | 22th Mar 1939 | Box 126 \ 2 scan0107 | |
| Weekend test run of a Humber Super Snipe car, model RC.7035. | 22th Mar 1939 | Box 126 \ 2 scan0108 | |
| Faults and performance characteristics of a vehicle during testing. | 22th Mar 1939 | Box 126 \ 2 scan0109 | |
| Road spring and suspension load data for a Humber Super Snipe. | 3rd Apr 1939 | Box 126 \ 2 scan0110 | |
| Specification sheet detailing spring rates, wheel movements, and spring hysteresis for a vehicle. | 3rd Apr 1939 | Box 126 \ 2 scan0111 | |
| Requesting a weight and construction analysis of a competitor's vehicle, the Humber Super Snipe. | 28th Apr 1939 | Box 126 \ 2 scan0112 | |
| With a sketch discussing a study of the head, connecting rod, and crankshaft damper. | 2nd May 1939 | Box 126 \ 2 scan0113 | |
| Request for particulars regarding the Humber Super Snipe vehicle. | 5th May 1939 | Box 126 \ 2 scan0114 | |
| Weight analysis comparing the Humber Snipe coachwork with a standard 4 1/4 Bentley all-steel body. | 10th May 1939 | Box 126 \ 2 scan0115 | |
| Letter from Humber Limited to W.A. Robotham requesting information and patent details on the 'Hayes' fan. | 25th May 1939 | Box 126 \ 2 scan0116 | |
| Request to dismantle a Humber Snipe car for detailed component analysis. | 26th May 1939 | Box 126 \ 2 scan0117 | |
| | | | |
