I worked as a Police Officer in Lancaster during the 1970's and spent a lot of time at the hospital dealing with staff and patient matters - whilst the building appears by modern day standards to be quite intimidating it was (and still is, with every credit to the builders who are currently converting it to housing) an impressive place.
As one of the earlier poster reports, the gardens were always magnificent; the place was airy without being cold (not sure what it was like when it first opened) and always seemed clean although the detergent smell was a little over powering. By all accounts when it opened it was a massive break through in social care and whilst some of the practices now appear barbaric I am sure our childrens children will think the same of some of the treatment we receive today to be similarly unnecessary.
So don't don't dwell on the fact that you had ancestors who spent time in this establishment. or others like it, particularly during it early days; they in some respect were fortunate to have such a facility - people elsewhere were still being left in the street to suffer.