"It was last used before the war," says Mr Sherrell, who is 88. "The bubbles refer to the springs that used to bubble up there."
When the group walked to the bottom of the field they found a decaying cylindrical stone structure with the remnants of a wooden door buried in the undergrowth. It was built directly over a spring, which was still there.
"The building's function was to keep cream and butter cool in the days before modern refrigerators were widespread," says Ian Kemp, who led the search party.
Rediscovering the Holbeton creamwell is the sort of event that brings delight to campaigners Susan Clifford and Angela King. The two, joint co-ordinators of Common Ground, the London-based environmental charity dedicated to preserving the "local distinctiveness of our countryside", have recently turned their attention to fields.
"Field Days is a national project in which we want to persuade people to look very hard at their local fields, and a good way to start is by studying the old field names, as the people did at Holberton," says Sue Clifford.
Bubbles Field is not an exceptionally unusual one, but it was still exciting for the Holbeton group to realise how it had gained its name by means of such a graphic example.
"Field names like Cuckoo Nook, The Vinegar Bottle, Saucer Field, Drumble Hangmans field, Long Friday, Teakettle Handlepiece and Wot Ground have similarly graphic titles, but it is rarely as easy as it was in Holbeton to trace their origins."
The importance of field names to Common Ground and many local historians is that they reveal the rich diversity of our landscape. While conservationists have been looking ever more closely at hedgerows, stone walls, flower meadows, ponds, trees and barns, they have often neglected to study the fields that gave rise to so many of these features, Ms Clifford points out.
"By rediscovering what their names mean we can encourage people to look after these fields", she says. "Like woods, they need using. All fields should do a job, which is why set-aside is so awful. By going back to the old name, known to locals and found in title deeds and on the maps of the Forties, we can often gain clues as to what the field was used for."
The names may also suggest future potential. For example, Blue Button Field. With a small change in management, a field with such a name may once again be a flourishing source of the wild scabious that provided its name.
Likewise any name that hints at the presence of water - such as "Bubbles" - might help drought-ridden farmers to solve some of their problems.
In 1994 the Herefordshire Field Name Survey Group, which is composed of volunteers from a a number of local history groups, won a British Archaeological Society Award for their research, which covered 260 parishes and more than 125,000 fields. Their finds have included a hitherto unknown motte and bailey castle in a field named "Castle Tump" in the village of Upton Bishop, near Ross-on-Wye.
A similar occurrence took place at Welton in Northamptonshire, where local enthusiasts discovered a motte and bailey previously not included in the British Historic Monuments Record.
"Tump" is one of the easier field names to interpret - it usually refers to a mound of some sort. However seemingly obvious, words can be deceptive as very often the meaning of a name has changed.
A good example might be "barrow". The word is pretty unlikely to refer to a wheelbarrow - they probably did not use them at the time these fields gained their names - bt people often assume this refers to a prehistoric burial site. However the old English names for "wood" and "hill" are very similar, and have been corrupted over the years into the word "barrow", so when the word appears in an old field name it does not necessarily signify the presence of a prehistoric burial site.
"Nevertheless, when a field bears this name it is in general worth investigating," says the appropriately named John Field, author of A History of English Field Names.
At Sulgrave Manor in Northamptonshire there are regular seasonal activities focusing on the surrounding fields, such as demonstrations of scarecrow- making, studying the old field names, making maps of them with local schoolchildren, and celebrating Apple Day in October. There are plans to incorporate the study of local fields in the national curriculum work they carry out in conjunction with local schools.
"We plan to grow a grain crop and also flax, which we can spin and weave, and also a crop of dye plants of some sort," says the deputy director, Maureen Jeffery. "So often, modern children do not associate food with crops any more, which is a shame. After all, in Tudor times, which is the period we concentrate on, most of the children round here would have worked on the land. We shall use no artificial fertilisers and only water from the stream, so the children can also learn to appreciate the consequences of crop failure."
Sue Clifford says: "We take it lying down when the French tell us that the soil of every wine slope in Burgundy produces a different flavour. In this country, just as much, crops taste differently from different land. Some of our fields have had four to five thousand years of work put into them. Rather than turning our backs on our fields we should take them more seriously, and encourage farmers to keep them in good heart."
As a start, Common Ground is trying to encourage local groups to act as "field marshals", who will try to alert local people to the riches present in so many old fields.
They hope that farmers and landowners can be persuaded to have the names of old fields painted or carved on their gates. Another idea is that people who have bought a building plot on what used to be a field may like to name their houses after the old field name.
"Field Days is about much more than field names," says Ms Clifford. "It is about raising everyone's awareness of the great richness of history, archaeology, buildings, artefacts, legends, folklore, names geology, soils, boundaries, plant and animal life - and the potential for wider use to be found in our fields."
'A History of English Field Names', by John Field, is published by Longman at pounds 15.99.
For literature on the Common Ground Field Days project send an A5 s.a.e.
to Common Ground, Seven Dials warehouse, 44, Earlham Street, London WC2H 9LA.