When colourless liquids are used, parallax mistake is avoided by use of Schellbach’s burette. On the inside wall opposite to graduation scale it has a melted in ribbon from milky glass in the middle of which a blue line is found. The level of liquid is now spotted very easily because of light breaking in the meniscus blue line now looks like a double spike.
Generalic, Eni. "Schellbach’s burette." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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