| Description | Date | Identifier | |
| Letter from C.C. Wakefield & Co. Ltd. arranging a visit to the Derby works. | 26th Jun 1930 | Box 32 \ 3 Scan190 | |
| Request for comparative viscosity testing of two different gear oils at various temperatures. | 3rd Oct 1930 | Box 32 \ 3 Scan191 | |
| The comparison of a suitable gearbox oil from Wakefields with the existing Amber 'A' oil. | 22th Oct 1930 | Box 32 \ 3 Scan192 | |
| From Paris to Derby regarding the viscosity of Wakefield Gear Oil. | 16th Oct 1930 | Box 32 \ 3 Scan193 | |
| Suitability of a gearbox oil from Wakefield's and enquiring about available alternatives. | 4th Nov 1930 | Box 32 \ 3 Scan194 | |
| Requesting a meeting with a Wakefield's technical representative regarding suitable gearbox oil. | 6th Nov 1930 | Box 32 \ 3 Scan195 | |
| Requesting a comparative analysis of Wakefield's Gearease No.1 against Whitmore's No.0 Hypoid Oil. | 18th Dec 1930 | Box 32 \ 3 Scan196 | |
| Order for Wakefield's Hypoid Axle Compound. | 10th Mar 1931 | Box 32 \ 3 Scan197 | |
| Testing and proposed use of an alternative oil for hypoid rear axles. | 10th Mar 1931 | Box 32 \ 3 Scan198 | |
| Letter from C.C. Wakefield & Co. to Mr. E. W. Hives arranging a meeting at the Derby works. | 17th Mar 1931 | Box 32 \ 3 Scan199 | |
| Requesting an order for Wakefields' No.I. Gear Ease oil for hypoid axles. | 28th May 1931 | Box 32 \ 3 Scan200 | |
| Inquiry to oil supplier C.C. Wakefield & Co. about the possibility of mixing their Gearease No.1 oil for use in gearbox testing. | 28th May 1931 | Box 32 \ 3 Scan201 | |
| Letter from C.C. Wakefield & Co., Ltd. regarding the thinning of No. 1 Gearease with the addition of Castrol 'XL' oil. | 2nd Jun 1931 | Box 32 \ 3 Scan202 | |
| Recommending a new, successfully tested alternative oil for hypoid rear axles. | 1st Sep 1931 | Box 32 \ 3 Scan203 | |
| Letter to C. C. Wakefield & Co. Ltd confirming the standardization of 'Gearease' oil for axle lubrication. | 19th Sep 1931 | Box 32 \ 3 Scan204 | |
| Letter from C.C. Wakefield & Co. Ltd. regarding the official recommendation of 'Gearease No. 1' lubricant. | 21th Sep 1931 | Box 32 \ 3 Scan205 | |
| Standardisation report on using Wakefields Gear Ease No.1 oil for hypoid gear rear axles. | 21th Sep 1931 | Box 32 \ 3 Scan206 | |
| Suitability of Wakefield's XXL oil as an alternative for gearbox lubrication. | 22th Oct 1931 | Box 32 \ 3 Scan207 | |
| From the Paris Showrooms to Derby regarding the equivalence of Castrol 'XXL' gear oil to Prices Amber 'A'. | 20th Oct 1931 | Box 32 \ 3 Scan208 | |
| Requesting a test of an alternative gearbox oil, XXL, from Wakefields. | 23th Oct 1931 | Box 32 \ 3 Scan209 | |
| Comparing the prices of three different lubricants for potential standardisation. | 28th Oct 1931 | Box 32 \ 3 Scan210 | |
| Internal request to order a 5-gallon drum of Wakefields Hypoid Axle Oil. | 30th Oct 1931 | Box 32 \ 3 Scan211 | |
| Request for a comparative analysis of two different gearbox oils. | 30th Oct 1931 | Box 32 \ 3 Scan212 | |
| Selection, pricing, and testing of hypoid axle oils from various suppliers. | 30th Oct 1931 | Box 32 \ 3 Scan213 | |
| Inquiry regarding the danger of mixing Castrol No. 1 Gearease with Whitmore's Compound. | 26th Nov 1931 | Box 32 \ 3 Scan214 | |
| Letter from C.C. Wakefield & Co. Ltd. regarding the mixing of lubricant compounds and a planned visit. | 23th Nov 1931 | Box 32 \ 3 Scan215 | |
| The delayed testing of a Rotary Transformer for E.A. Claremont Esq. | 24th Feb 1915 | Box 32 \ 4 Scan001 | |
| Plan showing the dimensions and calculations for a transformer's iron core, primary, and secondary windings. | 19th Aug 1919 | Box 32 \ 4 Scan002 | |
| Extract regarding the production testing of electrical apparatus and the acquisition of a transformer. | 19th Aug 1919 | Box 32 \ 4 Scan003 | |
| Requesting the modification of a transformer for production testing of condensers. | 9th Sep 1919 | Box 32 \ 4 Scan004 | |
| Winding specifications for an auto-transformer used in the production testing of condensers. | 4th Sep 1919 | Box 32 \ 4 Scan005 | |
| Calculations regarding the area of coils and clearance for a 220/450 transformer. | 17th Sep 1919 | Box 32 \ 4 Scan006 | |
| Urgent request to rewind a transformer for production testing of condensers. | 17th Sep 1919 | Box 32 \ 4 Scan007 | |
| Request for particulars of a transformer for testing insulating materials used in ignition coils. | 10th Dec 1930 | Box 32 \ 4 Scan008 | |
| Requirements for high-tension transformers needed for insulation testing. | 22th Sep 1920 | Box 32 \ 4 Scan009 | |
| Letter from Metropolitan-Vickers Electrical Co. Ltd. declining to quote for a testing transformer. | 1st Oct 1920 | Box 32 \ 4 Scan010 | |
| Letter from The British Thomson-Houston Co. Ltd. declining to quote for high tension transformers. | 5th Oct 1920 | Box 32 \ 4 Scan011 | |
| Letter from The British Electrical Transformer Co. Ltd. acknowledging an enquiry for an insulation testing transformer. | 9th Oct 1920 | Box 32 \ 4 Scan012 | |
| Quotation from Foster Engineering Co. Ltd. for two single-phase oil-cooled transformers. | 12th Oct 1920 | Box 32 \ 4 Scan013 | |
| Quotation from The British Electric Transformer Co. for transformers for insulation testing. | 18th Oct 1920 | Box 32 \ 4 Scan014 | |
| Continuation of a quotation from The British Electric Transformer Co. Ltd. outlining delivery and pricing terms. | 18th Oct 1920 | Box 32 \ 4 Scan015 | |
| Quotations for a transformer for insulation testing and suggesting alternative suppliers. | 26th Oct 1920 | Box 32 \ 4 Scan016 | |
| Required capacity of 1/2 to 1 K.V.A. and listing two company addresses. | 26th Oct 1920 | Box 32 \ 4 Scan017 | |
| Letter from W. Mackie & Co. clarifying they do not manufacture transformers in response to an enquiry. | 28th Oct 1920 | Box 32 \ 4 Scan018 | |
| Letter from Mitchell's Electrical & Wireless Ltd. acknowledging an enquiry for High Tension Transformers. | 29th Oct 1920 | Box 32 \ 4 Scan019 | |
| Quotation from Bowday & Co. for two oil-cooled transformers with variable secondary pressure options. | 30th Oct 1920 | Box 32 \ 4 Scan020 | |
| Quotation from H.W. Sullivan for insulation testing transformers. | 6th Nov 1920 | Box 32 \ 4 Scan021 | |
| Letter from Watson & Sons responding to an enquiry for a high tension transformer for insulation testing. | 13th Nov 1920 | Box 32 \ 4 Scan022 | |
| Specifications for a transformer used for insulation testing and observing 'Breakdown-voltage'. | 17th Nov 1920 | Box 32 \ 4 Scan023 | |
| Responding to a letter from Messrs. Watson & Sons regarding a high tension transformer for insulation testing. | 17th Nov 1920 | Box 32 \ 4 Scan024 | |
| Procurement process and supplier quotations for an insulation testing transformer. | 19th Nov 1920 | Box 32 \ 4 Scan025 | |
| Concluding the handover of correspondence for a particular matter. | 19th Nov 1920 | Box 32 \ 4 Scan026 | |
| Quotation from Mitchell's Electrical & Wireless Ltd. for two single-phase oil-cooled transformers and transformer oil. | 19th Nov 1920 | Box 32 \ 4 Scan027 | |
| Continuation page of a letter outlining guarantee, performance, and pricing terms, with alternative technical suggestions. | 19th Nov 1920 | Box 32 \ 4 Scan028 | |
| Quotation for an air-cooled transformer with an auto transformer regulated primary. | 19th Nov 1920 | Box 32 \ 4 Scan029 | |
| Quotation from Watson & Sons for an oil immersed insulation testing transformer. | 23th Nov 1920 | Box 32 \ 4 Scan030 | |
| Comparison table of transformer quotations from various suppliers. | 26th Nov 1920 | Box 32 \ 4 Scan031 | |
| Quotations and requesting the order of two transformers for insulation testing. | 1st Dec 1920 | Box 32 \ 4 Scan032 | |
| Purchase and cost of insulation testing apparatus. | 10th Dec 1920 | Box 32 \ 4 Scan033 | |
| Copy of a letter from Watson & Sons following up on a quote for an Oil Immersed Step Up Transformer. | 13th Dec 1920 | Box 32 \ 4 Scan034 | |
| Requesting an order for eight large batten lamp holders to be used for transformer insulation testing. | 16th Dec 1920 | Box 32 \ 4 Scan035 | |
| Need to acquire a High Tension (H.T.) testing transformer for the works. | 23th Dec 1920 | Box 32 \ 4 Scan036 | |
| Letter requesting information and particulars for a small transformer for testing insulating materials. | 30th Dec 1920 | Box 32 \ 4 Scan037 | |
| Letter from W. T. Glover & Co. Ltd. discussing testing transformers and voltage requirements for materials testing. | 5th Jan 1921 | Box 32 \ 4 Scan038 | |
| Letter from Royce Limited discussing the specifications of a transformer and insulating materials. | 19th Jan 1921 | Box 32 \ 4 Scan039 | |
| Letter discussing the properties and testing of a new varnish for impregnating induction coils. | 28th Apr 1922 | Box 32 \ 4 Scan040 | |
| From EFC to Hy. following up on the procurement of a High Tension (H.T.) Testing Transformer. | 28th Apr 1922 | Box 32 \ 4 Scan041 | |
| Chasing up several overdue jobs for the Electrical Experimental Department. | 7th Jul 1922 | Box 32 \ 4 Scan042 | |
| Order request for a single-phase oil-cooled transformer and transformer oil for testing insulating material. | 24th Aug 1922 | Box 32 \ 4 Scan043 | |
| Fault and unexpected terminals on a transformer for testing insulating materials. | 30th Oct 1922 | Box 32 \ 4 Scan044 | |
| Letter from Mitchell's Electrical & Wireless Ltd regarding diagrams for a supplied transformer. | 1st Nov 1922 | Box 32 \ 4 Scan045 | |
| Wiring diagram for a 1 KVA single-phase transformer showing H.T. and L.T. connections. | 18th Sep 1922 | Box 32 \ 4 Scan046 | |
| Wiring diagram showing the connections for an insulation testing transformer. | 31th Aug 1922 | Box 32 \ 4 Scan047 | |
| Filing cover page with a laboratory reference number and a print room date stamp. | 20th Nov 1933 | Box 32 \ 4 Scan048 | |
| Enquiry for a cutout and a choking coil to operate with a high tension transformer for the Experimental Department. | 21th Nov 1922 | Box 32 \ 4 Scan049 | |
| List of approximate alternating voltages from a transformer and their applications in various testing procedures. | 12th Sep 1924 | Box 32 \ 4 Scan050 | |
| Request to undertake the impregnation and baking of a testing transformer core. | 17th Sep 1924 | Box 32 \ 4 Scan051 | |
| Data table detailing the configurations and output voltages for a testing transformer. | 25th Sep 1924 | Box 32 \ 4 Scan052 | |
| Data table listing conditions, position of tappings, total number of turns, and equivalent nominal voltage. | 27th Sep 1924 | Box 32 \ 4 Scan053 | |
| Data table for transformer testing, showing tapping positions, total turns, and equivalent voltage. | 27th Sep 1924 | Box 32 \ 4 Scan054 | |
| Data table and schematic diagram for a tapped winding, detailing turn counts and corresponding voltages. | 29th Sep 1924 | Box 32 \ 4 Scan055 | |
| Requesting materials for winding an experimental testing transformer. | 29th Sep 1924 | Box 32 \ 4 Scan056 | |
| Calculations and specifications for a laboratory testing transformer. | 5th Feb 1925 | Box 32 \ 4 Scan057 | |
| Specification table for a testing transformer, detailing winding sections and voltages. | 8th Feb 1926 | Box 32 \ 4 Scan058 | |
| Specification table for a tapped electrical winding, detailing the number of turns, wire gauge, and nominal voltage for each section. | 8th Feb 1926 | Box 32 \ 4 Scan059 | |
| Table detailing specifications for coil windings by section, including the number of turns and nominal voltage. | 8th Feb 1926 | Box 32 \ 4 Scan060 | |
| Diagram of connections for a transformer switchboard. | 27th Feb 1926 | Box 32 \ 4 Scan061 | |
| Reverse of a document with a 'Print Room' stamp from Derby. | 27th Feb 1926 | Box 32 \ 4 Scan062 | |
| The magnetising flux density and stator currents of a variable frequency induction motor transformer. | 28th Oct 1929 | Box 32 \ 4 Scan063 | |
| Page describing the effect of low frequency on currents within a complete stator circuit. | 29th Oct 1929 | Box 32 \ 4 Scan064 | |
| Readings and observations for a variable frequency induction motor transformer with a three-phase stator to single-phase rotor. | 29th Oct 1929 | Box 32 \ 4 Scan065 | |
| Request to improve the accident proofness of an H.T. transformer by supplying an iron grid and a rubber mat. | 20th Feb 1930 | Box 32 \ 4 Scan066 | |
| Dynamometer testing of Havoline and Packard engine oils. | 25th Aug 1910 | Box 32 \ 4 Scan067 | |
| Extract regarding the satisfactory starting of an engine by hand magneto as on a Mercedes chassis. | 2nd Oct 1914 | Box 32 \ 4 Scan068 | |
| To Mr. Johnson detailing the results of a rough test comparing De Dion Oil with the standard Prices B oil. | 19th Sep 1910 | Box 32 \ 4 Scan069 | |
| Results of a De Dion oil test, its composition, and comparison with other oils. | 24th Sep 1910 | Box 32 \ 4 Scan070 | |
| Short typed memo regarding testing De Dion oil and future experiments. | 24th Sep 1910 | Box 32 \ 4 Scan071 | |
| Lubricating oils for car engines, gearboxes, and axles, and requesting recommendations. | 1st Sep 1919 | Box 32 \ 4 Scan072 | |
| Current prices and usage of various lubricating oils for car and aero engines. | 2nd Sep 1919 | Box 32 \ 4 Scan073 | |
| Cover note forwarding a letter from Messrs. Edgar Vaughan & Co. for necessary action. | 17th Dec 1919 | Box 32 \ 4 Scan074 | |
| | | | |