The sponge that would not grow

A sponge is one of the easiest animals in the world to propagate and one of the hardest to farm. Cut a living sponge into pieces, keep the pieces in clean moving water, and each piece will close its own wound and carry on as a whole animal. That much has been known since the nineteenth century. It is the rest of it that has defeated people.

The trouble is time. A cutting takes years to reach the size a buyer will pay for, and it spends those years fixed to one spot in open water, where it can be silted, stolen, warmed, scraped off by a storm, or killed by something nobody saw coming. A sponge farm is a field that cannot be fenced, cannot be moved, and will not tell you it has failed until the season you go to harvest it.

Why the divers were never replaced

The Aegean and the Gulf of Mexico both ran on diving, not farming, and they ran on it long after the arithmetic stopped making sense. Kalymnos sent men down in canvas suits and lead boots and lost some of them every year, and Tarpon Springs did the same with Kalymnian men who had crossed an ocean to do it. Everyone involved understood what the work cost. Farming was discussed the whole time. It kept not happening, because a family with boats and divers and a name in the trade has an asset that pays this year, and a sponge farm is a promise about the year after next.

Then in the middle of the twentieth century the sponge beds took a disease and the promise about the year after next became the only promise available. That is the moment the paper gets interesting. When a trade is healthy nobody writes anything down that they do not have to. When it is dying, everybody writes: applications, surveys, plot claims, letters to ministries, letters to cousins.

What a failed experiment leaves behind

This is the part I keep coming back to as a novelist. A successful business leaves a building. A failed experiment leaves paper, and the paper outlives everyone who understood it. Somewhere in a family's boxes there is a permit for a plot of seabed, and a hand-drawn chart with a compass bearing on it, and a receipt for cuttings, and nobody alive knows whether the plot was ever stocked or whether the money went somewhere else entirely.

A ledger that does not balance is not always a crime. Sometimes it is an experiment nobody finished explaining. That ambiguity is the engine of the Things Left Open novels: five heirs, five cities, and in every one of them a document that is either an accident or a decision, and a family that has already agreed which.

The Sponge Cache opens with a granddaughter counting mourners by their accents. It gets to the paperwork soon enough.