From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
List detailing the weights of three different silencer patterns and their drawing numbers.
| Identifier | ExFiles\Box 3\3\ 03-page014 | |
| Date | 30th November 1910 | |
| Silencer weights. Silencer latest pattern (tubes, etc) Drg. E-873 with silencer pipe lagged and silencer lagged 1/2-way up - Weight ------ 56 lbs. Silencer E-830 - Drg with silencer pipe entering silencer 12" lagged pipe and silencer lagged half-way up. Weight ----- 39 lbs. Silencer E-729 drg with silencer pipe lagged only Weight ----- 37 lbs 30-11-10 | ||