Research laboratory

Development of a laboratory apparatus

The incubator-stirrer: a very practical device!

In some research laboratories, it is sometimes necessary to stir solutions at a specific frequency and at a controlled temperature.

Discover the evolution of a device that is widely used in research laboratories: the incubator-stirrer.

By hand!Movie ClipMovie Clip
© Armand-Frappier Museum

By hand!

In the past, solutions were stirred by hand, as can be seen on this sequence from the early 1930s. It was very difficult to keep the incubation temperature constant, since the test tubes must be rapidly accessible so they can be stirred regularly.

In-house incubator-stirrerZoomZoom
© Armand-Frappier Museum

In-house incubator-stirrer

This device is used to stir liquids while keeping them at a given temperature. It was used in the laboratories of the Institut de Microbiologie et d'Hygiène de l'Université de Montréal between 1938 and 1958. It consists of a motor, a transmission belt, and a rack to agitate up to four tubes simultaneously. The horizontal metallic cylinders in which the tubes are placed turn when the motor is turned on. The black metallic sheath that surrounds the four metallic cylinders has two L-shaped openings. Rubber tubing linked to a source of cold or hot water, depending on the experiment, can be fixed on these openings. The water will circulate around the tubes stirred by rotation while keeping them at the desired temperature.

The incubator-stirrer todayZoomZoom
© Nicole Catellier, Cinémanima

The incubator-stirrer today

Today the incubator-stirrer is used to stir cultures and solutions contained in tubes or flasks placed on a rotating tray. The device is equipped with a thermostat to control and stabilize the temperature required by the experiment, and a ventilation system to make sure the temperature is as even as possible. The speed of rotation of the tray on which the tubes and flasks are deposited is also adjustable.