Claude Joseph Geoffroy was the brother of Étienne François Geoffroy

Étienne François Geoffroy

Étienne François Geoffroy , French physician and chemist, best known for his 1718 affinity tables. He first contemplated a career as an apothecary, but then decided to practice medicine. He is sometimes known as Geoffroy the Elder.-Biography:He was born in Paris...

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Like his brother, he was an apothecary

Apothecary

Apothecary is a historical name for a medical professional who formulates and dispenses materia medica to physicians, surgeons and patients — a role now served by a pharmacist and some caregivers....

 and chemist

Chemist

A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...

. Having a considerable knowledge of botany

Botany

Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...

, he devoted himself especially to the study of the essential oil

Essential oil

An essential oil is a concentrated hydrophobic liquid containing volatile aroma compounds from plants. Essential oils are also known as volatile oils, ethereal oils or aetherolea, or simply as the "oil of" the plant from which they were extracted, such as oil of clove...

s in plants.

He is known as Geoffroy the Younger to distinguish him from his brother, Geoffroy the Elder. However, this leads to confusion with his contemporary Claude François Geoffroy

Claude François Geoffroy

Claude François Geoffroy was a French chemist. He discovered the chemical element bismuth in 1753. Before this time, bismuth-containing minerals were frequently identified as either lead or tin ores....

(1729–1753) who is known as "Claude Geoffroy the Younger".