| Description | Date | Identifier | |
| Management and allocation of vehicles in the Experimental Department. | 1st Jul 1925 | Box 20 \ 11 Scan157 | |
| List of vehicles currently in the experimental department. | 25th Jun 1925 | Box 20 \ 11 Scan158 | |
| Quarterly note regarding the disposal of Hispano and Mercedes cars from the Experimental Department. | 7th Jul 1925 | Box 20 \ 11 Scan159 | |
| Explaining the continued use of Hispano and Mercedes cars for experimental purposes. | 8th Jul 1925 | Box 20 \ 11 Scan160 | |
| From 'Hs.' to 'B.J.' about providing an experimental car to 'E.' to accumulate mileage during a works closure. | 17th Jul 1925 | Box 20 \ 11 Scan161 | |
| Loaning a Phantom car fitted with experimental parts to an individual referred to as 'E'. | 20th Jul 1925 | Box 20 \ 11 Scan162 | |
| Authorizing the private use of car 98-NK for an individual to gain experience. | 21th Jul 1925 | Box 20 \ 11 Scan163 | |
| Seeking clarification on the rules for officials using experimental cars for personal journeys. | 22th Jul 1925 | Box 20 \ 11 Scan164 | |
| Letter of apology regarding the inability to arrange for the use of an experimental car. | 22th Jul 1925 | Box 20 \ 11 Scan165 | |
| Personal note arranging for a meeting in Burwash or Tunbridge Wells. | 22th Jul 1925 | Box 20 \ 11 Scan166 | |
| Arrangement of a Phantom car (98-NK) for 'E' to use for his holidays. | 22th Jul 1925 | Box 20 \ 11 Scan167 | |
| Letter declining a request for a holiday car due to concerns about experimental vehicles. | 23th Jul 1925 | Box 20 \ 11 Scan168 | |
| Requesting approval for applications to use experimental cars over the weekend. | 14th Aug 1925 | Box 20 \ 11 Scan169 | |
| Applications for the use of experimental cars over a weekend. | 14th Aug 1925 | Box 20 \ 11 Scan170 | |
| The current status and position of several vehicles. | 20th Aug 1925 | Box 20 \ 11 Scan171 | |
| Instructions to arrange a car for Lord Wargrave's journey from Harrogate to Liverpool and back. | 26th Aug 1925 | Box 20 \ 11 Scan172 | |
| Outlining the policy and guidelines for the running of experimental cars by company officials and assistants. | 1st Sep 1925 | Box 20 \ 11 Scan173 | |
| The second page of a typed letter concerning the convenience of preparing cars. | 1st Sep 1925 | Box 20 \ 11 Scan174 | |
| The running of experimental cars and noting an oversight in a previous communication. | 2nd Sep 1925 | Box 20 \ 11 Scan175 | |
| Recommending the creation of record cards for experimental cars sent for overhaul. | 1st Sep 1925 | Box 20 \ 11 Scan176 | |
| Correcting the omission of a name from a previous report regarding the running of experimental cars. | 1st Sep 1925 | Box 20 \ 11 Scan177 | |
| Requesting to be advised of chassis numbers and brief descriptions for future builds, where secrecy requirements allow. | 3rd Sep 1925 | Box 20 \ 11 Scan178 | |
| The completion of three experimental chassis: 8.EX, 7-EX, and 10-G-111. | 18th Sep 1925 | Box 20 \ 11 Scan179 | |
| List of cars in the experimental department, detailing their chassis, body, and specifications. | 1st Oct 1925 | Box 20 \ 11 Scan180 | |
| Status list of 20 HP cars and cars disposed of since the last list. | 10th Jul 1925 | Box 20 \ 11 Scan181 | |
| Sale of experimental Silver Ghost cars before the launch of the New Phantom model causes their price to depreciate. | 10th Jul 1925 | Box 20 \ 11 Scan182 | |
| The retention of a Silver Ghost type chassis in the Experimental Department. | 9th Oct 1925 | Box 20 \ 11 Scan183 | |
| The 46-PK car, detailing its history, condition, and transfer. | 18th Dec 1925 | Box 20 \ 11 Scan184 | |
| The potential disposal of specific company cars. | 21th Dec 1925 | Box 20 \ 11 Scan185 | |
| Future of company car GF-68, a 20 HP in the Experimental Department. | 21th Dec 1925 | Box 20 \ 11 Scan186 | |
| Agreement for staff to use experimental cars over the holiday. | 24th Dec 1925 | Box 20 \ 11 Scan187 | |
| Proposing the use of an experimental car during a holiday and seeking agreement. | 24th Dec 1925 | Box 20 \ 11 Scan188 | |
| Allocation of an experimental car in France for use by Sir James Percy. | 7th Jan 1926 | Box 20 \ 11 Scan189 | |
| Request for permission to use an experimental closed car for a weekend, with a handwritten approval. | 3rd Feb 1926 | Box 20 \ 11 Scan190 | |
| List detailing specifications and history of experimental cars. | 5th Mar 1926 | Box 20 \ 11 Scan191 | |
| List of specifications for a New Phantom model and various 20 HP engine and chassis configurations. | 24th Mar 1926 | Box 20 \ 11 Scan192 | |
| From CJ to Hs enquiring about a car trial in France. | 24th Mar 1926 | Box 20 \ 11 Scan193 | |
| The testing schedule and specifications for several experimental cars in France. | 26th Mar 1926 | Box 20 \ 11 Scan194 | |
| Plans for 10,000-mile tests of experimental cars in France. | 26th Mar 1926 | Box 20 \ 11 Scan195 | |
| From CJ to Hs asking if a car will be on trial in France around the 11th of April. | 24th Mar 1928 | Box 20 \ 11 Scan196 | |
| Quarterly note requesting a return showing all company cars and lorries at Derby and their usage. | 30th Mar 1926 | Box 20 \ 11 Scan197 | |
| Listing the status of experimental cars and recently disposed-of vehicles. | 1st Apr 1926 | Box 20 \ 11 Scan198 | |
| Stock taking list of experimental cars and chassis. | 13th May 1926 | Box 20 \ 11 Scan199 | |
| Stock-taking memorandum for experimental test engines and their valuation. | 13th May 1926 | Box 20 \ 11 Scan200 | |
| Quarterly note requesting a list of all company cars and lorries at the Derby site as of May 31st, 1926. | 1st Jun 1926 | Box 20 \ 11 Scan201 | |
| Listing the status and specifications of various experimental cars. | 4th Jun 1926 | Box 20 \ 11 Scan202 | |
| Quarterly note requesting a list of all company cars and lorries at the Derby site and their usage. | 25th Jun 1926 | Box 20 \ 11 Scan203 | |
| Listing experimental cars and their specifications or current status. | 1st Jun 1926 | Box 20 \ 11 Scan204 | |
| Quarterly note requesting a return showing all company cars and lorries at the Derby site and their purpose. | 30th Sep 1926 | Box 20 \ 11 Scan205 | |
| List of experimental cars with their chassis numbers, body types, and testing notes. | 2nd Oct 1926 | Box 20 \ 11 Scan206 | |
| The future sale of experimental cars. | 7th Oct 1926 | Box 20 \ 11 Scan207 | |
| The handover of experimental car 44-PK to the Repair Dept. for sale. | 30th Nov 1926 | Box 20 \ 11 Scan208 | |
| The experimental parts fitted to car 44-PK and instructions for their disposal. | 2nd Dec 1926 | Box 20 \ 11 Scan209 | |
| The sale preparation of Experimental Chassis No. 44-PK. | 1st Dec 1926 | Box 20 \ 11 Scan210 | |
| The completion of experimental work on the 5-EX Silver Ghost car and its handover to the R.D. | 9th Dec 1926 | Box 20 \ 11 Scan211 | |
| List detailing the location of experimental cars. | 13th Dec 1926 | Box 20 \ 11 Scan212 | |
| Requesting confirmation of rolling stock items not appearing on stock sheets. | 13th Dec 1926 | Box 20 \ 11 Scan213 | |
| Chasing the handover of the Late Experimental Chassis 5-EX. | 16th Dec 1926 | Box 20 \ 11 Scan214 | |
| Requesting the return of specific experimental electrical parts from chassis 5-EX. | 16th Dec 1926 | Box 20 \ 11 Scan215 | |
| Quarterly note requesting a report on all company-owned vehicles at Derby and their usage. | 30th Dec 1926 | Box 20 \ 11 Scan216 | |
| Listing the status of various experimental cars and fleet changes. | 30th Dec 1926 | Box 20 \ 11 Scan217 | |
| Status report on a list of experimental cars. | 12th Jan 1927 | Box 20 \ 11 Scan218 | |
| Continued list describing the body type and status of four 20 HP chassis. | 12th Jan 1927 | Box 20 \ 11 Scan219 | |
| Status report on various experimental cars, including 40/50 HP models and competitor vehicles. | 12th Jan 1927 | Box 20 \ 11 Scan220 | |
| List detailing the status and body type of four 20 HP vehicles. | 2nd Feb 1927 | Box 20 \ 11 Scan221 | |
| Requesting a statement of expenses for the Experimental Department for the years 1925-26. | 2nd Feb 1927 | Box 20 \ 11 Scan222 | |
| Quarterly note requesting a return of all company cars and lorries at Derby, including their specific usage. | 28th Mar 1927 | Box 20 \ 11 Scan223 | |
| Status report on a fleet of experimental and test cars. | 30th Mar 1927 | Box 20 \ 11 Scan224 | |
| Quarterly note requesting a return, in duplicate, detailing all company vehicles at Derby and their purpose. | 24th Jun 1927 | Box 20 \ 11 Scan225 | |
| Status report and list of various experimental cars. | 1st Jul 1927 | Box 20 \ 11 Scan226 | |
| Getting rid of a 20 HP car fitted with a Barker Landaulet body. | 1st Jul 1927 | Box 20 \ 11 Scan227 | |
| The condition and saleability of a 20 HP car, chassis 11-G-111. | 8th Jul 1927 | Box 20 \ 11 Scan228 | |
| Information about a car's delivery date due to a colleague's absence through illness. | 15th Jul 1927 | Box 20 \ 11 Scan229 | |
| The unavailability of a car for mileage testing, aside from experimental investigation. | 15th Jul 1927 | Box 20 \ 11 Scan230 | |
| Status update of five different vehicles or chassis. | 18th Jul 1927 | Box 20 \ 11 Scan231 | |
| Car requests for a holiday and proposing specific vehicle allocations. | 20th Jul 1927 | Box 20 \ 11 Scan232 | |
| Delaying the 10-EX car due to dissatisfaction, as it was intended for B.J.'s holiday. | 9th Aug 1927 | Box 20 \ 11 Scan233 | |
| Arranging for two cars to be at Gerrards Cross on a specific date and time. | 13th Sep 1927 | Box 20 \ 11 Scan234 | |
| Status report on various experimental cars, detailing their condition and purpose. | 30th Sep 1927 | Box 20 \ 11 Scan235 | |
| Quarterly note from EWT seeking replies on when various chassis can be scrapped or sold. | 7th Oct 1927 | Box 20 \ 11 Scan236 | |
| Quarterly note replying to questions about the status and experimental use of several cars and chassis. | 8th Oct 1927 | Box 20 \ 11 Scan237 | |
| High compression 20 HP car with a poor Windover body, suggesting its return to Derby. | 7th Sep 1927 | Box 20 \ 11 Scan238 | |
| Proposal regarding the disposal of the experimental Phantom car, 7-EX, used by Mr. Royce. | 16th Dec 1927 | Box 20 \ 11 Scan239 | |
| Short memo acknowledging receipt and promising action on the matter of Experimental Cars 7-EX after Christmas. | 19th Dec 1927 | Box 20 \ 11 Scan240 | |
| The status and usage of various experimental cars and other makes. | 4th Jan 1928 | Box 20 \ 11 Scan241 | |
| Experimental bodies and the condition and potential sale of car 93-NK with a Phantom engine. | 17th Jan 1928 | Box 20 \ 11 Scan242 | |
| Lord Wargrave's interest in an experimental or other car going in the direction of Spain. | 24th Feb 1928 | Box 20 \ 11 Scan243 | |
| The status and location of company cars used by the Experimental Department. | 25th Feb 1928 | Box 20 \ 11 Scan244 | |
| Experimental cars, testing schedules in France, and their suitability for Lord Wargrave. | 25th Feb 1928 | Box 20 \ 11 Scan245 | |
| Status and use of company cars, including the Hawk Northcliffe and Lancia Lambda. | 27th Feb 1928 | Box 20 \ 11 Scan246 | |
| Status report on experimental cars, detailing various models and their current condition or purpose. | 29th Mar 1928 | Box 20 \ 11 Scan247 | |
| Future of experimental car 15-EX after it was smashed up in France. | 5th May 1928 | Box 20 \ 11 Scan248 | |
| Recommendation to hand over the 17-EX chassis to sales, with an update on other sports type chassis. | 4th May 1928 | Box 20 \ 11 Scan249 | |
| Unsuitability of a 12-EX open-body car for the Chairman. | 5th May 1928 | Box 20 \ 11 Scan250 | |
| Feasibility of building the 15-EX into a long chassis. | 10th May 1928 | Box 20 \ 11 Scan251 | |
| Suggestions for rebuilding the 15-EX car, including chassis options and part compatibility. | 11th May 1928 | Box 20 \ 11 Scan252 | |
| Letter discussing the suitability of an open-body car for the Chairman's trip to Spain and the potential discomfort. | 18th May 1928 | Box 20 \ 11 Scan253 | |
| 10,000-mile test car for the Chairman and a potential 2,000-mile test in France. | 18th May 1928 | Box 20 \ 11 Scan254 | |
| Conflicting feedback and arrangements for further testing of the 14-EX car. | 18th May 1928 | Box 20 \ 11 Scan255 | |
| Providing a car for the Chairman's use in France, suggesting an experimental model. | 19th May 1928 | Box 20 \ 11 Scan256 | |
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