This is a lovely original Negretti & Zambra combined barograph and thermograph in need of some gentle restoration. I bought this from a private school in North London many years ago and it had originally been purchased new by the principal when the school opened in 1936.
 
First introduced in 1899, the extract from the trade catalogue circa 1910 describes this as...'A New Pattern Combined Baro, Thermograph and the handsome instrument very suitable for presentation, being simple to manage and very interesting....etc..' This example can be referred to as a Mk 2 version as it used the more stable bimetallic thermograph sensor and incorporates a neat gauze metal sheet  within the end glazed panel allowing air circulation into the movement. There are two interesting features of this advertisement; 1, it is priced at £12,12p which would be more than £1750 today and 2, the woodcut drawing of the instrument has somehow been reversed showing the clock drum on the right. One can only speculate how this error slipped through proof reading and the consequences following the printing!
 
Weekly charts and a fresh bottle of recording ink included and also a reprinted period pamphlet by Negretti & Zambra describing operating instructions and how to interpret typical chart recordings.
 
 
420mm W x 280mm D x 310mm H.