black
grey
blue
red
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For my part, I hold it equally impossible for a small shellfish to be produced without generation as for a whale to have its origin from the mud.

Antonie van Leeuwenhoek

I make the proportion of one of these small Water-creatures to a Cheese-mite, to be like that of a Bee to a Horse:
ANTONIE VAN LEEUWENHOEK

Bee Cheese Creature Horse Make Mite One Proportion Small Water
I observed certain animalcules, within whole bodies I saw so quick a motion as to exceed belief; they were about the size of a large grain of sand, and their bodies being transparent, that the internal motion could plainly be seen.
ANTONIE VAN LEEUWENHOEK

Animalclue Belief Body Certain Internal Land Motion Observe Quick Seen Size Transfer
How inscrutable and incomprehensible are the hidden works of Nature!
ANTONIE VAN LEEUWENHOEK

Earth Hide Nature Work
I have oft-times been besought, by divers gentlemen, to set down on paper what I have beheld through my newly invented microscopia, but I have generally declined.
ANTONIE VAN LEEUWENHOEK

Decline Invention Myself Paper Time
Man comes not from an egg but from an animalcule that is found in male sperm.
ANTONIE VAN LEEUWENHOEK

Animal Biology Born Man Science
The 31th of May, I perceived in the same water more of those Animals, as also some that were somewhat bigger.
ANTONIE VAN LEEUWENHOEK

Also Animal Bigger May More Perceive Same Somewhat Water
Whenever I found something remarkable, I have thought it my duty to put down my discovery on paper, so that all ingenious people be informed thereof.
ANTONIE VAN LEEUWENHOEK

Discover Information People Remark Responsibility Thinking
Among other things, I saw in the body of one of these animalcules a bright and round corpuscle, placed near the head, and in which a very wonderful swift motion was to be seen, consisting of an alternate extension and contraction.
ANTONIE VAN LEEUWENHOEK

Alternative Among Anmalcule ContrAction Head Moorningm Consist Place Swift Thing
I’ve spent more time than many will believe [making microscopic observations], but I’ve done them with joy, and I’ve taken no notice those who have said why take so much trouble and what good is it?
ANTONIE VAN LEEUWENHOEK

Believe Done Good Joy Make Microscopic More Much Observation Spent Time Trouble
I’ve spent more time than many will believe [making microscopic observations], but I’ve done them with joy, and I’ve taken no notice those who have said why take so much trouble and what good is it?
ANTONIE VAN LEEUWENHOEK

Believe Goodness Myself Observation Time Trouble
I have divers times endeavoured to see and to know, what parts the Blood consists of; and at length I have observ’d, taking some Blood out of my own hand, that it consists of small round globuls driven through a Crystalline humidity or water.
ANTONIE VAN LEEUWENHOEK

Blood Drive Humidity See Talk Time Water
For, the circumference of one of these little Animals in water, is not so big as the thickness of a hair in a Cheese-mite.
ANTONIE VAN LEEUWENHOEK

Big Cheese Circumstance Mite One Thickness Water
This particle I concluded to be the heart.
ANTONIE VAN LEEUWENHOEK

Conclude Heart Particle
The whole circumference of each of these streaks was about the thickness of a hair of one’s head. … all consisted of very small green globules joined together: and there were very many small green globules as well. [The earliest recorded observation of the common green alga Spyrogyra.]
ANTONIE VAN LEEUWENHOEK

Circumstance Consist Each Other Examining Globule Green Small Well Whole
I saw this vast number of animalcules not all through the semen, but only in the liquid matter adhering to the thicker part.
ANTONIE VAN LEEUWENHOEK

Adhere Animalcule Liquid Matter Number Part Saw Semen Thicker Through Vast
There was discover’d by me a fifth sort, which had near the thickness of the former, but they were almost twice as long. The first time bacteria were observed.
ANTONIE VAN LEEUWENHOEK

Bacteria Discover Fifth First Former Long Observe Sort Thickness Time Twice