Animals Quote by Antonie van Leeuwenhoek
“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.”
![“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)
![“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…” quote by Antonie van Leeuwenhoek](https://sms4smile.com/quotes/img-quotes/9f1/antonie-van-leeuwenhoek-17943_bacteria_the-4th-sort-of-creatures-which-moved-th_627470.jpg)
