Peering into the insides of a machine can be a useful way to learn about how it works. MBARI researchers Ken Johnson and Hans Jannasch created a transparent version of a profiling float, an instrument that makes biogeochemical measurements in the ocean, for educational purposes. To make the clear float, Jannasch collected old, discarded parts at MBARI and from partners at the University of Washington, and replaced the yellow outer casing of the float with a transparent PVC tube.
The inner parts are labeled and there are two cutaway elements—one to see the flow-cell, a device that allows seawater to be pumped over the sensors and shields the pH sensor from light, and another to see the bladder that inflates and deflates to allow the float to sink to the bottom and rise through the upper 2,000 meters of the open ocean, collecting measurements along the way. Jannasch, hailing from Germany, painted the cutaways red, a technique he remembers from his childhood when he saw an exhibit of a train that was cut in half in the Deutsches Museum in Munich.