A busy day today as we come to the end of the first week of our two-week dig in Forty Hall on the site of Elsyng Palace.

Today was our public open day, and we were pleased to welcome a steady stream of visitors all day, who joined us in scratching their heads at the impressive but somewhat enigmatic medieval/Tudor brickwork that was emerging from Trench 2.

Once we'd set up our displays and stalls, we finished exposing the brick floor in Trench 2, fully defining the edge of the wall that runs partly beneath it on its east side.

We also removed the rubble at the south end of the trench, which as expected revealed another wall under it. During this process it began to look as if there is another channel cut through the floor, although this one seems to have rubble in it rather than tiles like the other one - see the image to the right, and click here for an annotated version.

So, in this trench we currently have a brick floor surface, bounded on the south side by a wall, and with two parallel slots through it, with a second wall running partly beneath its east edge.

Since the floor is partially laid on top of it, the wall must pre-date the floor. The wall may therefore belong to the early 15th century phase of the palace as built by the Earl of Worcester, with the floor representing the extensive improvements made by Sir Thomas Lovell after his acquisition of the palace circa 1497.

Exactly what the floor and the channels are for is not yet clear. All this brickwork is along the back edge of the gatehouse, so we might expect the threshold to a rear entrance. In this case, the parallel channels may be the remains of beam slots that once supported a timber frame for something like a porch.

This theory was slightly confounded very late in the day, as we began to remove the jumble of roof tiles from the northern channel, only to find more tiles beneath, tightly mortared together. This begins to look as if the channel has been hastily and crudely blocked up - which you might expect of a drainage channel that went out of use.

There's still plenty more work to do on all of this to make things clearer, and a whole week to do it, including the continuing search for evidence of the 1960s trenches. Work continued in Trench 4 to that end today, and it is beginning to look unlikely that it contains 1960s backfill.

A day of excitement in Forty Hall today, but sadly for the wrong reasons.

A large grass fire broke out this afternoon on the east side of the lime tree avenue and rapidly spread, alarmingly initially towards the dig site.

A fortunate change in wind direction eventually carried the fire away to the east towards Maidens Bridge, before the London Fire Brigade arrived and were able to get it under control before it spread to any major groups of trees.

The first fire engine arrived very quickly and we were able to assist it onto the site, where its crew did an excellent job dousing the main flames, but a second engine was delayed by another call en-route, so EAS members lent a hand beating out and dousing smoldering hotspots with buckets of water from Maidens Brook, while the fire crew handled the main flame front.

Once the second engine arrived everything was quickly put out and the crews spent most of the rest of the day damping down the scene.

Meanwhile, back at the archaeological dig:

Just before all the excitement, we had just opened our fourth trench, about ten metres to the west of Trench 1, in another attempt to identify the complex of trenches first dug by the EAS in 1963-66.

This is as far west as we can go this year, and on the face of the available evidence we don't think the 60s work can have been significantly further west than this. If this trench draws a blank as Trench 1 did, we have a couple more options nearby, but our chances of finding the 60s work this year would start to seem really very slim, and we would need to seriously re-appraise our evidence for where the 60 work took place.

Things were much more optimistic in Trench 2, however, which is now rapidly producing a rich assortment of brickwork.

The rough brick surface we began to reveal yesterday is now almost entirely revealed, with a distinct edge along its west side. Where it enters the east section of the trench there is a rough tumble of bricks which may or may not be concealing a wall beneath. Just before it enters the west section (foreground of above image) there is a stack of tiles which look to be filling a slot through the surface. We can't tell yet if this is deliberate, for example a collapsed drain, or a coincidental tumble.

Along the east side of the brick surface (upper left in above image) there seems to be the remains of a wall, running on a different alignment to the surface, and we think beneath it (i.e. the brick surface is later and built on top).

There is a lot of work to do to make sense of all this and a lot of careful unpicking of rubble still to go, but the next major job in this trench will be planning and photography tomorrow morning, that is after we've set up all the gear for our public open day.

Let's hope it's not as much of a scorcher as today.

Day five of our two-week dig saw us turn away for the time being from our primary aim of relocating trenches dug in the 1960s, to our two secondary objectives, studying elements of the palace gatehouse building that we discovered last year.

Having proved yesterday that Trench 1 does not contain any evidence of 60s trenches, and not being able to safely dig any deeper into the rubble deposit due to the risk of section collapse, we have more or less done all we can in that trench for now.

We therefore redeployed our diggers to our secondary objectives. Trench 3, at the north side of the site, is intended eventually to reveal more of a wall junction seen last year, but for now there is still a fair amount of gravel and rubble to remove before we can expect results from it.

Meanwhile Trench 2, which has had a head-start, had the last of its post-palace landscaping pebbles removed early in the morning. Late yesterday afternoon we had got a hint of the anticipated brick surface, and sure enough as the afternoon wore on the few bricks we saw yesterday did indeed acquire several friends.

We haven't revealed the whole of the brick surface yet but it does seem to have at least one edge, which seems to be running towards where the expected wall ought to be. We're probably not deep enough to see the wall yet, so there remains plenty to do to understand this feature properly.

Apart from the masses of late 19th and early 20th century rubbish in Trench 1, there hasn't been a great deal in the way of finds so far but an eagle-eyed digger did spot a rather nice probably Mesolithic tool (probably a tool for piercing leather and/or animal skins) amongst the gravel being removed from Trench 3.

Quite a morale-booster and a reminder that hunting had been going on in Enfield for several thousand years before the Tudors.

Another largely unremarkable day today as we continued to make progress in trenches 1 and 2, albeit with a satisfying end to the day.

We slogged on all day in Trench 1, continuing to cut a preview slot along one side of it, in order to establish whether the undisurbed rubble deposit continues for its entire length.

We were able to confirm that it does - and so also that it lies beneath the brown deposit at the east end of the trench, which continued to produce all manner of extremely modern material including parts of a bicycle and even fragments of the proverbial kitchen sink.

The story of Trench 1 then seems to be a deposit of palace demolition rubble (circa 1660), filling a very deep feature such as a cellar or perhaps a moat - unfortunately whatever it is is too deep for us to safely excavate fully. Subsequently, likely during the nearby gas main installation in 1967, the ground was disturbed, perhaps by the driving through of an access road for the heavy machinery, and a lorry load of modern builder's rubbish was deposited on top.

As far as our objective of locating the 60s archaeologial trenches goes, this pushes the likely position further west. Whether or not we open another trench further west is yet to be decided.

Things were decidedly more interesting in Trench 2 however, as late in the day we finally began to reveal the anticipated brick surface.

This is the trench that is located next to a wall we saw last year, which had just a small exposure of what looked like a fragmentary brick surface next to it. This trench is intended to reveal more of the surface, and looks like it has begun to deliver the goods. We haven't had time to reveal much of it yet and we also hope to see more of the wall that the possible floor abuts, in due time.

We also removed topsoil from Trench 3, our other secondary target (see diagram) which we hope will reveal more of the wall junction we saw part of last year. This wall was about a metre deep, so it will be a while before we see any structures in Trench 3.

Not a great deal to report on day three of our 14-day dig on the site of Elsyng Palace.

Not much has changed from yesterday - in Trench 1 we continued to remove the browner deposit at the east end of the trench, that continued to yield a large amount of late 19th and early 20th century rubbish, and it continues to look as if this is overlying the compact layer of mortar and rubble we found at the west end of the trench.

The rubble layer is still very clean of finds and increasingly looks to be an in-situ post-palace demolition deposit and not a backfilled archaeological trench, which we had been looking for.

As the day wore on we cut a preview slot in the rubble and found it to extend to a depth of at least a metre - the last time we encountered a context like this it turned out to be the fill of a palace cellar. We have decided to extend this metre-deep preview slot to the entire length of the trench to confirm that the rubble layer extends that far. We won't be able to safely dig any deeper, but might possibly find an intact palace wall or two lurking in the rubble.

As far as locating the 1960s trenches goes, we may try one more throw of the dice later in the dig, by opening another trench a few metres further west, but that will depend on other factors such as weather and available manpower, and whether or not we do encounter any structures in Trench 1.

Meanwhile in Trench 2, we finished removing the pebble deposit and have begun to dig the brickearth and rubble layer that lies above the wall and possible floor surface that we found a corner of last year.

Hopefully it won't be long before we see our first Tudor wall of the dig - fortunately we know for certain there is one waiting for us in Trench 2!