No, it's not the clock tower of Hotham Park House, it was a separate one in approximately in the centre of the site. I read John Knowles' (founder of Marwell Zoological Park) autobiography recently and note that it was in fact he and Oliver Graham Jones, who had been the first full time vet at London Zoo who carried out the inspection that led to the closure of 'Zootopia', as it was then known. He paints bleak picture about what had become of it. His account of the bear escape is perhaps a little exaggerated for effect but the short section about 'Bognor Regis Zoo' is interesting. I found it reassuring that two such well regarded individuals gave the advise that saw the collection close, rather than the decision effectively being made by the council but did think it a little odd that Knowles inspected; not that Bognor Zoo would ever have given Marwell much to worry about but the two were probably the closest potentially rival animal attractions in the area at the time (with the possible exception of Gatwick).