Suggestions and diagrams for projecting sound great distances by means of small arms and parabolic reflectors.
Showing 1–7 of 7 items
Suggestions and diagrams for projecting sound great distances by means of small arms and parabolic reflectors.
The theoretical considerations that JH would take into account if he were going to study the subject of 'increasing and conveying to great distances and in given directions the reports of guns or other explosive instruments, as signals.'
A note probably accompanying JH's 1852-3-23. Comments concerning someone's collection.
William Lassell wishes to go to Malta to observe the heavens, and would like a letter of introduction to the governor there. Can FB assist with this?
Reports quite unsatisfactory results from gun firing sound experiments [see JH's 1852-3-23].
Urges that Thomas Maclear's son be appointed to assist Maclear in the observatory [at the Cape].
Will instruct Smith, Elder & Co. to provide a presentation copy of JH's Cape Results to Queen's College, Belfast. What has happened with JH's recommendation about Thomas Maclear's son [see JH's 1852-6-11]?