This large stone building on Chesterfield Road was first known as the Poplar Cottage Hydropathic Establishment (trading as Thomas Davis and Sons)^[1]; it became Jeff's Poplar Hydro some time after 1902 as George Davis was given as "of Poplar Cottage" when his Will was proved in that year^[2]. The family retained it for a couple of years^[1].

When it was sold again in 1912 it had become Jeffs Poplar Hydro Company Limited^[3] and was described as "all that freehold land, situate in Chesterfield-road, Matlock, in the county of Derby, with the messuage or dwellinghouse, used as a hydropathic establishment, bathhouses, electric power house and other buildings erected thereon, known as Jeffs Poplar Hydro, and the business of a hydropathic establishment and boarding house, heretofore carried on on the above premises by the defendant company, and the goodwill and connections thereof, stock-in-trade, furniture, plate, glass, china, stores, baths, fittings and appliances, wood-constructed motor garage and other effects in and about the said house and premises. A small portion of the property is copyhold of the Manor of Matlock"^[4].

It was later was renamed Chatsworth Hydro^[5] and continued as a hydro until the Second World War when C&A Modes, a Manchester textile firm, took it over (although it was still advertising as a hydro in Kelly's 1941 Directory). Chatsworth reopened briefly as a hydro post war but was bought by Derbyshire County Council along with Rockside and a number of large houses. These buildings all became part of Matlock Teacher Training College, which was a highly respected institution. Unfortunately for the town, the students eventually moved to the Derby when the Derby and Matlock Colleges amalgamated.

References (coloured links to onsite information):

^[1] Information from Ray Ash. Also see the 1891 census when Josiah Davis was at Poplar Cottage and "Kelly's 1891 Directory" listing Davis Thomas & Sons, hydropathic establishment, Prospect House & Poplar Cottage. Not on this site, but the same entry was in "Kelly's Directory 1895 "; by 1899 the entry was for Thos Davies & Sons and was just Poplar Cottage
^[2] "The London Gazette", 28 February 1902
^[3]"Kelly's Directory, 1908" advertised Jeff's Poplar Hydro Co. Limited (Miss E. Trolley, manageress), Chesterfield road and in the 1912 directory William F. and Mrs. R. Hides were the managers
^[5] "The London Gazette", 17 September 1912 (notice of sale of property).
^[4] "Kelly's Directory, 1925" gives the name as Chatsworth Hydro and the 1932 version states that Chatsworth Hydropathic Co. Ltd was "under new ownership & management ... adjacent to golf links"

There is additional information available on-site:

Thomas Davis advertised in "Days in Derbyshire" (1863) by Spencer Timothy Hall. Hall also mentions the Davis brothers in Chapter 5
Matlock Bank Primitive Methodist Church, 'Young Mens' Class has pictures of some members of the Wildgoose family, who were related to the Davis family
Matlock Primitive Methodist Prize Choir also shows some of the Wildgoose family
Water Cures All about the hydros and hydropathy
Quick List Names in Census returns and Trades Directories
In 1901 Grimsby Town football team were staying at Poplar Hydro on census night