the entire bridge, measuring from the extreme front of the wing walls, is 1,833 feet, and its greatest elevation at Britannia pier, 240 feet above low-water-mark. The total cost of the structure is L601,865. This wonderful structure was begun April 13, 1846, and completed July 25, 1850; opened for traffic Oct. 21, 1850. [Illustration: [++] The Britannia Tubular Bridge.] DAFFEY'S ELIXIR. In the _Postboy_, Jan. 1, 1707-8, is the following curious advertisement:--"Daffey's famous _Elixir Salutis_ by Catherine Daffey, daughter of Mr. Thomas Daffy, late rector of Redmile, in the valley of Belvoir, who imparted it to his kinsman, Mr. Anthony Daffy, who published the same to the benefit of the community and his own great advantage. The original receipt is now in my possession, left to me by my father. My own brother, Mr. Daniel Daffy, apothecary in Nottingham, made the Elixir from the said receipt, and sold it there during his life. Those who know it, will believe what I declare; and those who do not, may be convinced that I am no counterfeit, by the colour, taste, smell, and operation of my Elixir. To be had at the Hand and Pen, Maiden-Lane, Covent Garden." JENNY'S WHIM. "This was a tea garden, situated, after passing over a wooden bridge on the left, previous to entering the long avenue, the coach way to where Ranelagh once stood. This place was much frequented, from its novelty, being an inducement to allure the curious, by its amusing deceptions, particularly on their first appearance there. Here was a large garden, in different parts of which were recesses; and if treading on a spring, taking you by surprise, up started different figures, some ugly enough to frighten you--a harlequin, a Mother Shipton, or some terrific animal. In a large piece of water, facing the tea alcoves, large fish or mermaids, were showing themselves above the surface. This queer spectacle was first kept by a famous mechanist, who had been employed at one of the winter theatres, there being then two."--Angelo's _Pic Nic or Table Talk_, p. 106. Horace Walpole, more than once alludes to this place of entertainment in his Letters; and in 1755 a 4to. satirical tract appeared entitled _Jenny's Whim; or a Sure Guide to the Nobility, Gentry, and other Eminent Persons, in this Metropolis_. ANECDOTE RELATIVE TO THE MASKED EXECUTIONER OF CHARLES I.