'The chimney-valves are part of a set of means devised by me for ventilation under all circumstances. My report on the ventilation of ships, sent at the request of the Board of Health, has been published in the Board's late Report on Quarantine, with testimony furnished to the Admiralty as to its utility in a convict ship with 500 prisoners. My observations on the ventilation of hospitals are also in the hands of the Board, but not yet published. All the new means have been freely offered to the public, but persons desiring to use them should be careful to employ competent makers.' Having seen Dr Arnott's ventilators in operation in London and elsewhere, we can venture to recommend them as a simple and very inexpensive machinery for ventilating rooms with fires. The process is indeed generally known, and would be more extensively applied if people knew where to procure the ventilators. We have had many letters of inquiry on this subject, and could only refer parties to 'any respectable ironmongers.' But unfortunately, as it appears, there are hundreds of respectable ironmongers who never heard of the article in question, and our recommendation goes pretty much for nothing. Curious how a little practical difficulty will mar a great project! We trust that the worthy doctor will try to let it be known where his ventilators are to be had in town and country. AN OLD-FASHIONED DITTY. I've tried in much bewilderment to find Under which phase of loveliness in thee I love thee best; but oh, my wandering mind Hovers o'er many sweets, as doth a bee, And all I feel is contradictory. I love to see thee gay, because thy smile Is sweeter than the sweetest thing I know; And then thy limpid eyes are all the while Sparkling and dancing, and thy fair cheeks glow With such a sunset lustre, that e'en so I love to see thee gay. I love to see thee sad, for then thy face Expresseth an angelic misery; Thy tears are shed with such a gentle grace, Thy words fall soft, yet sweet as words can be, That though 'tis selfish, I confess, in me, I love to see thee sad. I love to hear thee speak, because thy voice Than music's self is yet more musical, Its tones make every living thing rejoice; And I, when on mine ear those accents fall, In sooth I do believe that most of all I love to hear thee speak. Yet no! I love thee mute; for oh, thine eyes Express so much, thou hast no need of speech! And there's a language that in silence lies, When two full hearts look fondness each to each, Love's language that I fain to thee would teach, And so I love thee mute. Thus I have come to the conclusion sweet, Nothing thou dost can less than perfect be; All beauties and all virtues in thee meet; Yet one thing more I'd fain behold in thee-- A little love, a little love for me. MARIAN.