The document discusses the history of the microscope from its early inventions in the 16th century to its modern applications. It describes key figures like Hans and Zacharius Janssen who invented the compound microscope in the 1590s and Anton van Leeuwenhoek who greatly improved lens grinding and was the first to observe bacteria and other microorganisms in the 1670s-1680s using simple microscopes of his own design. The development of more powerful compound microscopes and eventually electron microscopes allowed scientists to make new biological discoveries by observing cells and microscopic structures.

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4. SCI TRIVIA

5. SCITRIVIA

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10. History of the
Microscope

11. I. Microscope
An instrument that makes
small objects look larger.
A. The Inventors:
1. 1590 Hans &
Zaccharius Janssen
a. Dutch lens grinders
b. made the 1st compound
microscope (has more than
one lens)

12. 2. 1609 Galileo
a. Improved on the
Janssen’s ideas
b. Made a
microscope that
could be focused

13. 3. Anton Van Leeuwenhoek
1632-1723
a. Dutch scientist who
greatly improved lens
grinding
b. 1st to see bacteria,
yeast, blood cells, and
life in pond water
c. Made people aware of
microscopic life

14. And now, time out
for a word from
your sponsor….

15. Leeuwenhoek
Unlikely
scientist
 A tradesman (a
fabric merchant, a
surveyor, a wine
assayer, and a
minor city official)
 No university
degrees
 Knew no language
other than Dutch

16. …oh Leeuwenhoek
 But he had skill, he was hardworking,
had an endless curiosity, and he kept
an open mind
 His researches opened up the world of
microscopic life to scientists

17. His Inspirations…
 Leeuwenhoek saw Robert Hooke’s
illustrated book Micrographia which
showed Hooke’s own observations with
a microscope

18. Anton Van Leeuwenhoek’s 1632-1723
 Made over 500 simple “microscopes”
 Microscopes were simply powerful
magnifying lenses
 Specimens were mounted on the sharp point
that sticks up in front of the lens
 A tradesman (a
fabric merchant, a
surveyor, a wine
assayer, and a
minor city official)
 No university
degrees
 Knew no language
other than Dutch
 Leeuwenhoek saw Robert Hooke’s
illustrated book Micrographia which showed
Hooke’s own observations with a
microscope
• Dutch scientist who greatly
improved lens grinding
• 1st to see bacteria, yeast,
blood cells, and life in pond
water
• Made people aware of
microscopic life

19. Anton’s Microscopes:
 Compound microscopes invented around 1595
 But could only magnify 20-30x
 But Leeuwenhoek’s simple microscope could
magnify 200x (what a great lens grinder)!
 Hired a skilled illustrator to draw the things he
saw

20. All good researchers
share their findings….
 1673 Leeuwenhoek began writing
letters to the Royal Society of London
describing what he’d seen with his
microscopes

21. Eeeeewww…
 17 September 1683 wrote about
observations on his own plaque “a little
white matter, which is as thick as if it
‘twere batter”
 Repeated observations on two men who
had never cleaned their teeth
 Found “an unbelievingly great company
of living animalcules, a-swimming more
nimbly than any I had ever seen up to this
time. Moreover…the animalcules…
seemed to be alive.”

22. WEE BEASTIES!
 These were the first observations of living
bacteria ever recorded!
 He soon called them his “wee beasties”!

23. Oooh What He Saw!
Foraminifera
Blood cells

24. CONGRATULATIONS
ANTON!
 After 50 years of
writing to the Royal
Society of London,
he was elected a full
member
 Joined Robert
Hooke, Robert Boyle,
Christopher Wren
and other great
scientists of his day

25. …Now, back to
your notes…

26. B. Compound Light Microscope
1. Has two or more lenses
2. Used to study cells
3. Most magnify to 400x
4. Most powerful magnifies 2000x
5. Most have 3 objectives
a. Low
b. Medium
c. High
6. Specimen MUST be thin
(allows light to pass through)

27. C. Electron Microscope
1. Uses electrons and
magnets
2. Very powerful –
magnifies 2 million x or
more
3. Show specimens in 3-D
4. Requires TV to view
image

28. 1. Which of the following is NOT
one of the people credited with
inventing the microscope?
A. Hans LippersheyNot Quite!
B. Marie CurieCorrect!
C. Hans JanssenNot Quite!
D.Zacharias Janssen

29. 2. All of our _____________ exist
because of our ability to study
illnesses through the lens of a
microscope.
A. Illnesses
B. Cells
C. Medicines
D. Protein

30. 3. Which of the following is the BEST evidence that
microscopes have greatly improved over time?
A. “The first microscopes made by the Janssens
magnified objects by nine times. Today, the world’s
strongest microscope helps us see objects at 200,000
times their size!”Correct!
B. “One tool that helps people understand the world
more clearly is the microscope.”Not Quite!
C. “Looking through the tube, they found that it made
objects on the other end look bigger! Another eyeglass
maker named Hans Lippershey made a similar tool
around the same time.”Not Quite!
D. “Microscopes have helped people learn a lot about
our world.”

31. 4-5. Why is it that
microscopes were considered
an important tool used by
biologists in conducting their
laboratory research?

32. Thank You!