| Description | Date | Identifier | |
| Filter sent for inspection purposes on a sale or return basis. | 7th Dec 1940 | Box 136 \ 3 scan0109 | |
| Letter from The Institution of Automobile Engineers regarding a figure for gallons of oil needed for a discussion on Mr. Worth's paper. | 10th Dec 1940 | Box 136 \ 3 scan0110 | |
| Requesting an update on the decision regarding the sale or return of an oil filter. | 11th Dec 1940 | Box 136 \ 3 scan0111 | |
| Letter from British Filters Ltd discussing the suitability of by-pass versus centrifugal filters and requesting drawings for design DES.220. | 17th Dec 1940 | Box 136 \ 3 scan0112 | |
| Rm to HH requesting detail drawings for DES.220. | 20th Dec 1940 | Box 136 \ 3 scan0113 | |
| Request for detail drawings for fitting by-pass oil filters to old type Bentley cars. | 10th Nov 1941 | Box 136 \ 3 scan0114 | |
| Letter to Messrs Simmonds Accessories Ltd regarding the replacement of By-Pass Filters on pre-war models. | 17th Nov 1940 | Box 136 \ 3 scan0115 | |
| Letter from Simmonds Aerocessories requesting engine layout and lubrication information from Bentley Motors. | 7th Nov 1940 | Box 136 \ 3 scan0116 | |
| Letter from Air-Maze confirming a meeting regarding oil filters for 27-litre engines. | 21th Jan 1941 | Box 136 \ 3 scan0117 | |
| From 'Rm' to Mr. Hooker recommending a filter fabricator for a development project. | 25th Feb 1941 | Box 136 \ 3 scan0118 | |
| Letter from British Filters Ltd. regarding a new design of filter for low viscosity oil. | 19th Feb 1941 | Box 136 \ 3 scan0119 | |
| Letter to British Filters Ltd. regarding a sample filter delivery, support brackets, and a revised layout for a filter on a Bentley. | 27th Feb 1941 | Box 136 \ 3 scan0120 | |
| Letter to British Filters Ltd. requesting a set of parts for an experimental B.II car, with specific size requirements. | 28th Feb 1941 | Box 136 \ 3 scan0121 | |
| Fitting a General Oil Filter to a B.11 chassis, detailing a parts list and design feedback. | 27th Feb 1941 | Box 136 \ 3 scan0122 | |
| Letter from British Filters Ltd concerning difficulty sourcing small brass pipe fittings and requesting supplier suggestions. | 11th Apr 1941 | Box 136 \ 3 scan0123 | |
| Letter to British Filters Ltd. regarding the production of small parts for filters. | 19th Apr 1941 | Box 136 \ 3 scan0124 | |
| Inquiring about alternative suppliers for parts, likely filters, due to capacity issues with Rotherham's. | 19th Apr 1941 | Box 136 \ 3 scan0125 | |
| Telegram requesting an oil pump be sent by passenger train due to inability to arrange road transport. | 25th Apr 1941 | Box 136 \ 3 scan0126 | |
| Letter to British Filters Ltd. regarding filter restriction tests and delivery curves for Merlin oil pumps. | 30th Apr 1941 | Box 136 \ 3 scan0127 | |
| Graph showing delivery curves for Merlin engine oil pumps against engine RPM. | 13th May 1941 | Box 136 \ 3 scan0128 | |
| Request for instructions on the quantity of kits required to place an official order with British Filters Ltd. | 13th May 1941 | Box 136 \ 3 scan0129 | |
| Letter to British Filters Ltd. regarding an order for half-a-dozen kits for 3 1/2 and 4 1/4 litre Bentleys. | 20th May 1941 | Box 136 \ 3 scan0130 | |
| Order to be placed with British Filters Ltd for fitting kits. | 20th May 1941 | Box 136 \ 3 scan0131 | |
| Letter to Messrs. Vokes Ltd. requesting a drawing of an air cleaner. | 16th Jun 1941 | Box 136 \ 3 scan0132 | |
| Confirming payment agreement for a filter from British Filters Ltd and requesting a covering works order number. | 17th Jun 1941 | Box 136 \ 3 scan0133 | |
| Letter confirming a telephone conversation regarding an unreceived order from British Filters for filter components and providing an update on other castings. | 19th Jun 1941 | Box 136 \ 3 scan0134 | |
| Letter to British Filters Ltd. regarding filtration jobs and acquiring a filter for a tank. | 21th Jun 1941 | Box 136 \ 3 scan0135 | |
| Brief cover letter to T.C. Worth of British Filters Ltd. regarding an enclosed letter. | 16th Jul 1941 | Box 136 \ 3 scan0136 | |
| The loan of an Auto-Clean filter unit to British Filters for examination. | 18th Jul 1941 | Box 136 \ 3 scan0137 | |
| Returning a loaned 'General' oil filter to British Filters Ltd. | 22th Jul 1941 | Box 136 \ 3 scan0138 | |
| Confirming the return of a 'General' oil filter to its makers, British Filter, Ltd. | 23th Jul 1941 | Box 136 \ 3 scan0139 | |
| Design, availability and fitting of a British Filters oil filter to a Bentley car. | 20th Sep 1941 | Box 136 \ 3 scan0140 | |
| Letter from British Filters Ltd providing an analysis of two oil samples. | 25th Sep 1941 | Box 136 \ 3 scan0141 | |
| Request to order three Schrader tyre pressure gauges for the 'GOSHAWK' 10,000 miles trials. | 2nd Feb 1922 | Box 136 \ 3 scan0142 | |
| The Dunlop foot pump lacking a pressure gauge and the proposal to supply a separate 'Schrader' pattern gauge. | 3rd Oct 1922 | Box 136 \ 3 scan0143 | |
| Supply of tyre pressure gauges for the 40/50 and 20 HP model tool kits. | 4th Oct 1922 | Box 136 \ 3 scan0144 | |
| Arranging for Schrader tyre pressure gauges to be included in the 20 HP and 40/50 tool kits. | 4th Oct 1922 | Box 136 \ 3 scan0145 | |
| Suggestion to include a Schrader Tyre Pressure Gauge and accessories in vehicle tool kits. | 24th Oct 1922 | Box 136 \ 3 scan0146 | |
| Clarifying the price for a Schrader Gauge pump connection and the complete gauge. | 7th Nov 1922 | Box 136 \ 3 scan0147 | |
| Urgent inquiry regarding the standardization of the Schrader Right Angle Tyre Pressure Gauge for G.11 Production. | 15th Nov 1922 | Box 136 \ 3 scan0148 | |
| Schrader right-angle tyre valve connections compared to slip-on rubber connections. | 16th Nov 1922 | Box 136 \ 3 scan0149 | |
| Schrader right-angle connections and a collection of tyre gadgets. | 17th Nov 1922 | Box 136 \ 3 scan0150 | |
| Schrader tyre pressure gauge, related pricing sheets, and its long-term usage. | 21th Nov 1922 | Box 136 \ 3 scan0151 | |
| Cover note attaching a copy of a memo and requesting a reply. | 21th Nov 1922 | Box 136 \ 3 scan0152 | |
| Querying the standardization of a Schrader Tyre Pressure Gauge for G.11 Production. | 15th Nov 1922 | Box 136 \ 3 scan0153 | |
| Cover note regarding communication from the Schrader Company about gauges and pump connections, requesting a Standardisation Sheet. | 23th Nov 1922 | Box 136 \ 3 scan0154 | |
| Letter from A. Schrader's Son Inc. regarding the merits of screwed tyre valve connections over slip-on rubber types. | 20th Nov 1922 | Box 136 \ 3 scan0155 | |
| The transfer of a Dunlop Low Pressure Tyre Gauge between departments. | 1st Jan 1924 | Box 136 \ 3 scan0156 | |
| Asking for instructions regarding a Dunlop Low Pressure Gauge. | 9th Jan 1924 | Box 136 \ 3 scan0157 | |
| Request for a reply concerning a Dunlop Low Pressure Gauge that is no longer required. | 23th Jan 1924 | Box 136 \ 3 scan0158 | |
| Letter to John F. Warwick apologising for a delayed reply and discussing indicators for testing. | 14th Jan 1925 | Box 136 \ 3 scan0159 | |
| Letter acknowledging receipt of a Tyre Pressure Indicator for testing. | 30th Jan 1925 | Box 136 \ 3 scan0160 | |
| Letter from a customer about a modification to pressure indicators and tyre pressure. | 2nd Feb 1925 | Box 136 \ 3 scan0161 | |
| Requesting the return of a faulty and inaccurate Dunlop low pressure gauge. | 27th Aug 1925 | Box 136 \ 3 scan0162 | |
| Internal request to order tyre pressure gauges for various tyre brands. | 9th Sep 1925 | Box 136 \ 3 scan0163 | |
| Supply of Schrader Tyre Gauges and recommending a more accurate model for the tool kit. | 27th Aug 1929 | Box 136 \ 3 scan0164 | |
| The specifications and ordering of a new Schrader tyre gauge. | 30th Aug 1924 | Box 136 \ 3 scan0165 | |
| Discontinuance of a 70 to 75 lbs tyre gauge and its replacement. | 30th Aug 1929 | Box 136 \ 3 scan0166 | |
| Requesting test results for a 'Kismet Tyre Tester' and advice on purchasing a 'Schrader Gauge'. | 25th Sep 1929 | Box 136 \ 3 scan0167 | |
| Modifying Schrader tyre pump gauges with a 45° angle for use with disc wheels. | 10th Feb 1930 | Box 136 \ 3 scan0168 | |
| Correcting the suggested angle for Schrader Tyre Pump Gauges to 45 degrees. | 11th Feb 1930 | Box 136 \ 3 scan0169 | |
| Introduction and evaluation of a new 'Trutest' tyre pressure gauge. | 16th Oct 1930 | Box 136 \ 3 scan0170 | |
| Proposal to standardize a new Schrader Trutest Pressure Gauge. | 12th Dec 1930 | Box 136 \ 3 scan0171 | |
| Confirming the satisfactory test of a Schrader Trutest pressure gauge. | 21th Jan 1931 | Box 136 \ 3 scan0172 | |
| Test report and comparison of the Kismet '31 Tyre Tester against the Schrader gauge. | 4th May 1931 | Box 136 \ 3 scan0173 | |
| Recommendation to replace the Schrader tyre pressure gauge with the cheaper, better-made, British 'Kismet' gauge. | 5th May 1931 | Box 136 \ 3 scan0174 | |
| Replacement of the Schrader gauge with the Kismet '31 tyre tester. | 19th May 1931 | Box 136 \ 3 scan0175 | |
| Standardisation document for the '31 Kismet Tyre Tester, proposing it as a replacement for the Schrader gauge. | 21th May 1931 | Box 136 \ 3 scan0176 | |
| On testing a sample 'A.P.' model tyre pressure gauge and comparing it to the existing Kismet type. | 26th Feb 1935 | Box 136 \ 3 scan0177 | |
| Need for a more compact and less bulky tyre pressure gauge. | 21th Mar 1935 | Box 136 \ 3 scan0178 | |
| Requesting a report on a sample new tyre pressure gauge from A. Schrader's Son. | 21th Mar 1935 | Box 136 \ 3 scan0179 | |
| Comparison of different tyre pressure testers, with a preference expressed for the Kismet Gauge. | 27th Mar 1935 | Box 136 \ 3 scan0180 | |
| Rejecting Tyre Testers from Walters & Dobson, stating a preference for Kismet gauges. | 15th Jun 1935 | Box 136 \ 3 scan0181 | |
| New model of tyre gauge from the supplier Wm. Turner & Bro. Ltd. | 31th Oct 1936 | Box 136 \ 3 scan0182 | |
| Requesting 3 dozen Schrader Tyre Valve cores in tin boxes of 5. | 5th Nov 1936 | Box 136 \ 3 scan0183 | |
| Testing and proposed replacement of a standard gauge with a new, lighter Kismet type gauge. | 12th Nov 1936 | Box 136 \ 3 scan0184 | |
| Recommending the replacement of the standard gauge with a new, lighter Kismet type gauge from Wm. Turner & Bro. Ltd. | 12th Nov 1936 | Box 136 \ 3 scan0185 | |
| Approval and re-ordering of tyre pressure gauges from a supplier. | 12th Nov 1936 | Box 136 \ 3 scan0186 | |
| Letter from Pneumatic Components Ltd regarding the addition of a tyre valve key to their tyre gauge. | 19th Dec 1938 | Box 136 \ 3 scan0187 | |
| Letter to Pneumatic Components Ltd regarding feedback on a sample tyre gauge being tested. | 24th Jan 1939 | Box 136 \ 3 scan0188 | |
| Letter from Pneumatic Components Ltd acknowledging a communication regarding a sample Tyre Gauge. | 26th Jan 1939 | Box 136 \ 3 scan0189 | |
| Letter from Pneumatic Components Ltd regarding the design and sampling of tyre gauges. | 30th Jan 1939 | Box 136 \ 3 scan0190 | |
| Letter from the Experimental Department to Pneumatic Components Ltd. arranging a meeting. | 1st Feb 1939 | Box 136 \ 3 scan0191 | |
| Requesting the return of a pressure gauge for repair or replacement. | 9th Aug 1940 | Box 136 \ 3 scan0192 | |
| Request to return a Hopkinson pressure gauge for repair, or to obtain a new one if it is beyond repair. | 22th Jan 1941 | Box 136 \ 3 scan0193 | |
| Page from 'The Motor' magazine reviewing the 1911 Olympia Motor Show, discussing worm drives and showcasing various mechanical features. | 14th Nov 1911 | Box 136 \ 4 scan0001 | |
| Article from 'The Motor' magazine describing the Lentz Hydraulic Transmission Gear. | 14th Nov 1911 | Box 136 \ 4 scan0002 | |
| Article from 'The Motor' magazine describing the Lentz transmission gear system. | 14th Nov 1911 | Box 136 \ 4 scan0003 | |
| Article from 'The Motor' magazine discussing the Lentz hydraulic transmission gear. | 14th Nov 1911 | Box 136 \ 4 scan0004 | |
| Departmental memo requesting an opinion on the Lentz gear. | 2nd Jan 1912 | Box 136 \ 4 scan0005 | |
| Departmental memo requesting committee opinions on the Lentz hydraulic gear. | 8th Jan 1912 | Box 136 \ 4 scan0006 | |
| Potential benefits of the Lentz hydraulic gear and suggesting practical tests. | 9th Jan 1912 | Box 136 \ 4 scan0007 | |
| Departmental memo requesting and providing opinions on the Lentz hydraulic gear. | 8th Jan 1912 | Box 136 \ 4 scan0008 | |
| To Mr. Barrington explaining the calculated efficiency of the Lentz Hydraulic System. | 15th Jan 1912 | Box 136 \ 4 scan0009 | |
| The disadvantages of the Lentz Hydraulic Transmission system. | 15th Jan 1912 | Box 136 \ 4 scan0010 | |
| Technical analysis of the issues and principles of hydraulic transmissions, with a focus on the Lentz gear system. | 15th Jan 1912 | Box 136 \ 4 scan0011 | |
| Page concluding against the use of the Lentz hydraulic gear due to its operational disadvantages. | 15th Jan 1912 | Box 136 \ 4 scan0012 | |
| Extract from Mr Bailey's Olympia Report on a Dr Lentz hydraulic transmission system. | 15th Jan 1912 | Box 136 \ 4 scan0013 | |
| Comparison of the Hele Shaw system against the Lentz system and ordinary mechanical change gear. | 23th Oct 1923 | Box 136 \ 4 scan0014 | |
| Report by Mr. Bailey on the estimated efficiency of the Lentz Hydraulic System. | 15th Jan 1912 | Box 136 \ 4 scan0015 | |
| | | | |
