I have often endeavoured to view the circulation of the blood in terrestrial animals, but without success, by reason that no parts of their bodies were sufficiently transparent. Antonie van Leeuwenhoek Read Quote
In rain water, I observed a small red worm and two other kinds of very minute insects; of those of the larger size, I judged that 30,000 together would not equal a coarse sand. Antonie van Leeuwenhoek Read Quote
I have lately examined water, in which beaten pepper was steeped, and found two sorts of animals for shape, and each of those sorts to contain greater and smaller kinds: the greater I supposed the elder, the less the younger. Antonie van Leeuwenhoek Read Quote
Just as the supposed number may differ from the true number by fully 100, 150, or even 200 in a flock of 600 sheep, so may I be even more out of my reckoning in the case of these very little animalcules. Antonie van Leeuwenhoek Read Quote
For my part, I would say that the male sperm and seeds of plants have been penetrated so far that there is nothing further to discover in this great secret, but I could err in my opinion. Antonie van Leeuwenhoek Read Quote
I’ve never taught one, because if I taught one, I’d have to teach others… I would give myself over to a slavery, whereas I want to stay a free man. Antonie van Leeuwenhoek Read Quote
If we now plainly perceive that the passage of the blood from the arteries into the veins of the tadpole is not performed in any other than those vessels, which are so minute as only to admit the passage of a single globule at a time, we may conclude that the same is performed in like manner in our own bodies and in those of other animals. Antonie van Leeuwenhoek Read Quote
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 Read Quote
We will admit that, out of the mud or sand which is found on the seashore or the beds of our rivers, at low water, shellfish or testaceous animals come forth, but it does not from thence by any means follow that they are produced without any regular course of generation. Antonie van Leeuwenhoek Read Quote
