Credit: ©The Royal Society
    Image number: RS.15439

    Modification of an air pump

    Date
    2 February 1663
    Creator
    Unknown, Artist
    Object type
    Archive reference number
    Manuscript page number
    p1
    Material
    Dimensions
    height (page): 351mm
    width (page): 251mm
    Subject
    Physics
       > Vacuum physics
          > Pneumatics
    Content object
    Description
    A sketch of a 'pneumatic engine' (air pump) designed by Christian Huygens, with lettering to indicate its parts.

    This is most likely the enlarged copy from the original letter from Huygens to Robert Moray dated 2 February 1663 [New Style] (EL/H1/18). The copy was ordered, along with an English translation of the text (EL/H1/19), at the meeting of the Royal Society on 28 January 1663 [Old Style]. The paper was read the following week on 4 February 1663.

    Other copies of this image can be found at LBO/1/077 and LBC/1/093.
    Transcription
    Text on back of page: Mr Huygens pneumatic Engine
    Transcribed by the Making Visible project
    Object history
    At the meeting of the Royal Society on 28 January 1663, ‘Sir Robert Moray having mentioned his having received a letter from Monsieur Huygens, it was ordered, that an English translation of it be made against the next meeting, and that the scheme contained in it be drawn in great’ (Birch 1:192).

    On 4 February 1663, ‘Monsieur Huygens’s letter to Sir Robert Moray, dated from the Hague, February 2, 1662/3, was read; and the experiments mentioned therein, viz. that of the quicksilver sticking to the finger, and that of the not subsiding of water purged from air, were recommended to be made again; the former to Dr. Goddard, in a cane of a less bore than formerly; the latter to Mr. Hooke’ (Birch 1:193).

    Oldenburg's translation of the letter reads, ‘The Figure will easily make you understand it [=the engine]. The sucker, as you see, is drawn upwards, but not further than A; the space AB being about 2 inches, which you must imagine to be full of water mixt with oyle, so that this liquor descends and riseth with the sucker, and thereby hinders the ingresse of Air into the Cylinder; but lets only enter a little of the said water and oyle, when the sucker is not altogether just: which afterwards goeth out at the little vent C: the cock is on the side of the Cylinder in E, to which is joined the pipe EH, which on the other end is soddered [=soldered] to the little dish FG, wherein there is Cement, to fasten the recipient upon. The figure shews all, so that tis needless to speak any more of it. When you let the Engine rest, the liquor, remaining in the space AZ, keeps the sucker from growing dry, so that it may be always found fit for use. To make, that the sucker shall not rise higher than A, I stop with lead an iron-Nutt OP. To exclude the Air of the Recipient after it is exhausted (which is that you look chiefly for) I find nothing better, than to put the Recipient on soft cement (whereof I have formerly spoke to you) and to wrap the Cock about with leather: for by this means I find no fault in it but very seldom; whereas I think it almost impossible with hard cement’ (EL/H1/19).
    Related fellows
    Christiaan Huygens (1629 - 2006, Dutch) , Natural philosopher
    Associated place
    <The World>
       > Europe
          > Netherlands
    Powered by CollectionsIndex+/CollectionsOnline