Typescript and manuscript annotated draft reports including 'Bulk Milk Tank Dairy Heat Pump', 'Refrigerated Farm Tanks', 'Water Heating Potential of Refrigerated Farm Tanks', 'Super Heat and the Development of a High Temperature Hot Water Recovery System', 'Simulated Farm Trials 1963-1964', 'The design and operation of Heat Recovery Units for use with Refrigerated Farm Tanks', 'Refrigerant Properties: Value of the Mollier Diagram', 'Superheat Tests Spring 1962', 'Conversion of Standard Refrigeration System to Water Heating', 'Inchurn milk cooling and water heating by Refrigeration'. There are also diagrams, notes, graphs, bibliography and tables of data. The file includes a published copy of 'Which Bulk tank?' by JB Hoyle (NIRD Paper No. 3002, January 1966), as well notes and annotations added at a later date by A.S. Cromarty.