Hamwell is a small hamlet, in the parish of Wheathampstead, and close to No Mans Land Common, just off the road between Sandridge and Wheathampstead. It is often possible to find out where someone was living by looking at the neighbours in the census book - see Locating Census Addresses on Maps.

If you look at the 1871 census on Ancestry you will find that Caroline Spring was described as a "publican & straw plaiter" living at Hamwell - and there is no difference between a publican who only sells beer (i.e. does not sell wine or spirits) and a beerhouse keeper. In fact in most villages there were many beerhouses - where the local labourers would drop into the front room for a glass of beer by the open fire. It was common for many beerhouse keepers to do another job as well.  Unfortunately the trade directories rarely give the names of the beerhouses. The 1866 Post Office Directory lists 15 beerhouses in Wheathampstead, six named public houses, and two brewers.

Often people in small hamlets were closely related and I note that three adjacent households in Hamwell were headed by Caroline Spring (59 year old widow), Sussana [sic] Spring (a 75 year old spinster) and Thomas Munt (a 55 year old agricultural labourer and his family).

There are web pages for Wheathampstead, No Mans Land and Straw Plait

If you can add to the information given above tell me.