Jigsaw 11, Series 3, Notice B

Close of business, Tuesday, 29th December.

The jigsaw is now more than half complete. Aim to complete it tomorrow.

Unusually, the mode of completion has been more from the outside in, rather out than from well defined features in the middle.

Linear features, captured from patterns which can be seen on individual pieces, now more or less complete. Luckily, there are quite a lot of these.

The two isolated blobs of interior have, in the closing minutes of the day, been linked to the shore.

The various modes of operation are now coming back into mind. First, identifiable patterns on individual pieces. Second, colour matching. I had forgotten how important this one is. And how relative colour is - sometimes looking very different in the heap than it does in position. Third, distinctive or distinctly positioned holes or prongs. Fourth, sorting by piece shape and trying each in the target position in turn. This last is effective but tedious; very much a last resort.

Good, natural light is helpful. So the light in the east facing front room is good in the morning, the back extension where the jigsaw is gets better late morning, early afternoon. So we have to make do with not very good electric light a lot of the time.

The subconscious seems to do a lot of the work. It does most of the selection of target positions. One then looks at the target position, tries to fix the search key in mind, then scans around the loose pieces, very roughly sorted. Then look back at the target to refresh the search key. Then, from time to time, the right piece just comes to hand. If nothing doing, after a while go for a new target position.

Sometimes one finds pieces without having a target position in mind. One sees a piece and the brain just knows where it goes. Generally when one has been working on a puzzle for a while.

Note that, ideally, each target position is defined by at least two other pieces, in which case error is very unlikely. Definition by one other piece, sometimes necessary, particularly when pushing out linear features, is much more risky. Luckily, no mistakes so far - mistakes being a pain to unpick.

Note that this is a regular puzzle with four pieces meeting at every interior corner. Puzzles which are irregular in this sense are both unusual and much harder.

The bad news is that the top right hand corner is still missing. Maybe the whole corner fell off during the packing process. Given that this is a one-off puzzle, with the buyer supplying the image, maybe quality control is not as strong as it would be a for a series.

Reference 1: psmv4: Jigsaw 11, Series 3, Notice A.