Anyone who has gone in the field regularly, however, will tell you that no amount of planning will prevent the unexpected from happening. This is when creativity can make or break an experiment. One instance when creativity proved to be useful was on a recent research expedition on board the RV SONNE. After almost 7 weeks at sea, sampling supplies on ship were running low. To sample sediment cores, cut-off syringes were used to draw some sediment and were then capped. Unfortunately, we ran out of caps and cores were still being collected.

As I was thinking of a simple way to cap the syringes without contaminating the sediment with the glue from the tape, it occurred to me that lab gloves ought to be made of material that would not contaminate the samples. We ended up cutting the fingers of some lab gloves (we had plenty of those), in order to pull them over the syringes and secure them with tape. This was simple enough and served our purpose!

The true syringe lid on the left, the improvised lid on the right.

All of these instruments make in-situ measurements. But sometimes there is no instrument capable of measuring the quantity we are interested in (radioactive isotopes concentration, bacterial analysis, etc). That is why we use Niskin bottles to take water samples. They are tied open in the wet lab and then remotely triggered to seal shut and trap water at a given depth. But you have to make sure you fire these bottles on the way up! If a bottle is sealed on the way down, the extra pressure at depth, compared to the pressure of the sampled water, is going to crush the bottle. While on the way up, the extra pressure of the trapped water can be released without contaminating the water sample.

Once the rosette is back on deck, we transfer the required volume of water into labeled bottles for future processing in the laboratory.