The fieldgate at the south had barbed wire either side of the top and the way there is spongy - so go through the farm. A small area of stones exposed in the eastern side has no order apparent unless the top few are a real line.
Finally able to have a good look at the cut in the northern end (no compass so, mound very roughly aligned with long axis NS but probably only following [present] cliff edge). Not even superficially a quarry, and Orkney has some decidedly rum bits mapped as this. Slightly more circular than rectangular when you're in it. Not sure if the back is a continuous arc, more like angled stone lines either side. And if these are a wall still unsure if truly curved or straight walls distorted by erosion. Probably artefact of unrecorded prior excavation or else resulting from digging out circular feature such as a round cairn
What I thought to be a decorated stone is more likely to be natural. Behind the cut is the reported 15m depression that has led to its identification as a possible broch. Then I was on top of the cut and not far from this is an orthostat seen from the coast. And it is part of a feature highly reminiscent of that at the top end of the round cairn inserted into Head of Work, which Davidson and Henshall contend is likely the top of a chamber. even if this is incorrect it is definitely nothing a Brochaholic would accept as to do with a roundhouse. What you first note are two orthostats of a size on order with that at the top of the cut - maybe half-a-metre or so high - and three feet across the pair, with a jumble of flat stones of various sizes tumbled in front for about five feet and layered. If these are the backstops the chamber is roughly aligned EW and running at right angles to the long axis- so unlike the Head of Work in this respect too. On closer inspection there are further orthostats a couple of inches behind the 'backstops', though rather than something like packing these may be more of the backstops themselves heavily fragmented, indicating depth to my mind.
There's the top of a long rectangular stone that looks to form most of the southern edge, with a longitudinal split that indicated it goes down a fair piece - to the feature's floor perhaps. There are several other thick stones exposed, flat on the mound but partially buried nevertheless. Two of these solidly sunken near the eastern side, not flat but the tops of probable orthostats. These look to be at right angles to each other. Though they are exposed two or three inches away one from another they could well form a real pair under the earth.
From the hill above the Mill of Ireland this and Cummi Howe broch and The Cairns 'Danish fort'/castle look equidistant - though it is 8m from the cliff edge the other sites could have suffered more erosion, one tideswept and the other ? subject to undercutting - and there were three brochs on the other side of the water too. From the road the hollow appears less central. Short of Outbrecks I followed the track down to the north end of Cumminess Bay. There is a gate into the NW corner of the field containing Corn Hillock but my main purpose was to see the known broch, so as yet I have only viewed it from the coastal fence. At this end of the bay there is a rather lage area covered by loose large stone blocks of fairly regular shape that have all the appearance of being artificial, which made me think of the the stones dumped into the sea from the Work Broch in St.Ola (and from whatever lay by/under St.Nicholas Church in Holm). Though I then walked along the low clifftop it is a little intermittent and I would suggest going along the shore mostly. It simply has not the feel of a broch in my mind. Only a few stones can be seen in the coastal side until you approach the north end, where I noticed what seems to be an overgrown trench (either excavated or for sheltering stock I think) with various sorts of stone around the likely sides. These are mostly horizontal slabs, perhaps evidence of drystane walling - but I wish I had gone in to inspect as my images show up on the southern end a large ? orthostat and low down on the northern end a rectangular sandstone block that may have an incised line around the face of it. The orthostat's position is an unlikely one in a broch (my hazard would be pre or post "Broch Age") and the block resembles ones I connect with early kirks (there is one in a wall by Long Howe that has to come from St.Ninian's Chapel and another in the Sands of Wideford bridge I take to have come from Essonquoy). Best guess from me is that Corn Hillock is the result of two periods of construction.
This grassy mound (corn here means 'cows'), RCAHMS record no. HY21SE 99, does not appear to have had specific mention prior to the 1998 coastal survey (assuming the cairn below Cumminess referred to in 1907 is Cummi Howe broch). It is some 33m by 20m and 1.6m in height. They found stone concentrations at various places and some protruding earthfast stones, also evidence of quarrying about the edge. EASE hazards that it is the remains of some kind of settlement, perhaps a broch because of an apparent 15m central hollow.