Archive · 2 Oct 2026
Jagadish Chandra Bose's Crescograph Made Plant Growth Visible
Plants grow so slowly that people usually cannot see them moving.
Jagadish Chandra Bose wanted to measure these tiny changes.
He built a device called the crescograph.
The machine made very small movements at a plant's growing tip much larger.
It could record the movement as marks that scientists could study.
One version magnified movement 10,000 times, while a magnetic version could magnify it millions of times.
Bose used the instrument to investigate how plants reacted to things such as light, temperature and chemicals.
His invention helped turn invisible plant growth into measurable scientific evidence.
Indian scientist Jagadish Chandra Bose developed the crescograph in the early 20th century to measure extremely slow plant growth.
The instrument used mechanical and optical systems to magnify tiny plant movements thousands of times.
Its high-magnification version used two 100-fold levers, producing 10,000-fold magnification.
Bose later developed a magnetic crescograph and reported magnifications reaching millions of times.
His work helped scientists quantitatively study plant growth and responses to light, temperature, chemicals and other stimuli.
- Who
- Indian physicist and scientist Jagadish Chandra Bose.
- What
- He developed the crescograph, an instrument that magnified and recorded tiny plant movements.
- When
- In the early 20th century; his high-magnification work was submitted in 1917 and published in 1919.
- Where
- Bose worked at Presidency College in Calcutta and later established the Bose Research Institute.
- Why
- Plant growth was too slow to observe easily, so Bose sought to measure how plants responded to external stimuli.
- Inventor
- Jagadish Chandra Bose
- Birth
- 30 November 1858, Mymensingh
- Instrument
- Crescograph
- Mechanical magnification
- 10,000 times, using two 100-fold levers
- Magnetic magnification
- Bose reported magnifications reaching millions of times
- Royal Society timeline
- Work submitted in 1917 and published in Proceedings of the Royal Society B in 1919
- Research focus
- Plant growth, movement and responses to light, temperature, chemicals and other stimuli