I have divers times examined the same matter (human semen) from a healthy man... not from a sick man... nor spoiled by keeping... for a long time and not liquefied after the lapse of some time... but immediately after ejaculation… — Antonie van Leeuwenhoek Copy Share Image
The 31th of May, I perceived in the same water more of those Animals, as also some that were somewhat bigger. And I imagine, that [ten hundred thousand] of these little Creatures do not equal an ordinary grain of Sand… — Antonie van Leeuwenhoek Copy Share Image
If any person examines by the microscope that part towards the extremity of the spider's body from whence its thread proceeds, he will observe… — Antonie van Leeuwenhoek Copy Share Image
In rain water, I observed a small red worm and two other kinds of very minute insects; of those of the larger size, I… — Antonie van Leeuwenhoek Copy Share Image
I have often endeavoured to view the circulation of the blood in terrestrial animals, but without success, by reason that no parts of their… — Antonie van Leeuwenhoek Copy Share Image
In treating of the oak, I have considered that the species of it growing in warm climates is superior to that which is produced… — Antonie van Leeuwenhoek Copy Share Image
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. Among other things, I saw in the body of one of these animalcules a bright and round corpuscle, placed… — Antonie van Leeuwenhoek Copy Share
Whenever I found something remarkable, I have thought it my duty to put down my discovery on paper, so that all ingenious people be… — Antonie van Leeuwenhoek Copy Share Image
Man comes not from an egg but from an animalcule that is found in male sperm. — Antonie van Leeuwenhoek Copy Share Image
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… — Antonie van Leeuwenhoek Copy Share Image
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… — Antonie van Leeuwenhoek Copy Share Image
Whenever I found out anything remarkable, I have thought it my duty to put down my discovery on paper, so that all ingenious people… — Antonie van Leeuwenhoek Copy Share Image
The 4th sort of creatures... which moved through the 3 former sorts, were incredibly small, and so small in my eye that I judged, that if 100 of them lay [stretched out] one by another, they would not equal the length of a grain of course Sand; and according to this estimate, ten hundred thousand of them could not equal… — Antonie van Leeuwenhoek Copy Share
How inscrutable and incomprehensible are the hidden works of Nature! — Antonie van Leeuwenhoek Copy Share Image
![“The 31th of May, I perceived in the same water more of those Animals, as also some that were somewhat bigger. And I imagine, that [ten hundred thousand] of these little Creatures do not equal an ordinary grain of Sand in bigness: And comparing them with a Cheese-mite (which may be seen to move…” quote by Antonie van Leeuwenhoek](https://sms4smile.com/quotes/img-quotes/a1e/antonie-van-leeuwenhoek-17943_animal_the-31th-of-may-i-perceived-in-the-same_2552391.jpg)
![“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?” quote by Antonie van Leeuwenhoek](https://sms4smile.com/quotes/img-quotes/5b8/antonie-van-leeuwenhoek-17943_believe_i-ve-spent-more-time-than-many-will-beli_560375.jpg)
