That which I claim is first forming the longitudinal joint or valve of the Pneumatic or propelling Tube of Atmospheric Railways by means of one or more flexible tubes which are made elastic and yielding by inflating them with air or other fluid or by any other convenient means the said flexible tubes being arranged in such a manner that they shall always keep the valve closed by maintaining the flexible tubes in perfectly air tight contact with each other, except during the passage of the piston, or when only one flexible tube or less is employed by maintaining it in contact with a soft and slightly yielding cushion as above described –
Dr Sir,
Above is a Copy of what you require we find that “Scotch and Irish” specifications were enrolled for Hallettes <1> Invention. –
We are Your obed Servt
Poole & Carpmael
Notes:
1. Alexis Hallette (1788–1846), engineer of Arras. [See Doc. No: 05525].