1. "All matter is made up of small indivisible particles called atoms."
2. "It may be remarked that if we cannot always discover the causes of things, we can sometimes discover the laws to which they are subject."
3. "In science, the credit goes to the man who convinces the world, not to the man to whom the idea first occurs."
4. "Atoms cannot be seen, but we infer their existence and properties from the ways in which substances behave."
5. "The laws of chemical combination are the best evidence of the existence of atoms."
6. "Chemical analysis and synthesis go no further than to the separation of particles one from another, and to their reunion."
7. "The simplicity of nature is not confined to the atom."
8. "The elements, if arranged according to their atomic weights, exhibit an apparent periodicity of properties."
9. "Every particle of matter was divided into small indivisible parts or atoms."
10. "This paper will no doubt be treated by chemists with the same indifference as all my former communications have been."
11. "It is one of the first duties of a professor to advance the knowledge of his subject."
12. "The pressure of an atmosphere is nothing but the weight of the fluid above the point where it is exerted."
13. "It appears to me that one great defect of our chemical knowledge is that we have not yet ascertained the relative weights of the ultimate particles of bodies."
14. "No two particles of matter are exactly alike."
15. "When atoms combine to form molecules, they do so in fixed and definite proportions."
16. "I should indeed like to see a comparison between the actual and calculated weights of atoms."
17. "If we consider the subject of heat abstractedly, we may regard it as a substance capable of mixing itself with all other bodies."
18. "The doctrine of definite proportions is, I believe, by far the most important of all which chemistry owes to its immediate connection with atomic philosophy."
19. "The atoms of the same element are alike in all respects, including weight; atoms of different elements have different weights."
20. "I have chosen the title of this work with much deliberation, and I wish to avoid the appearance of advancing anything beyond the established facts of chemical science."
21. "My observations led me to the conclusion that the particles of vapour of elastic fluids are surrounded by an atmosphere of heat, and that they mutually repel each other."
22. "The weight of an atom of any one element is a constant quantity."
23. "The vast complexity of chemical combinations, together with the order and regularity with which they are arranged, naturally suggests the idea of a plan."
24. "The real existence of the simplest bodies which are indivisible by any known method of analysis has long been established by chemists."
25. "It is clearly established that the particles of bodies mutually attract each other with forces that are inversely as some power of the distance."
26. "The study of heat is one of the most interesting branches of physical science."
27. "By far the most important object of chemistry is the determination of the relative weights of the ultimate particles of bodies."
28. "From the observation of a great number of bodies, it appears that the relative weights of the ultimate particles of gases are simple multiples of that of hydrogen."
29. "The study of gases has led to the discovery of many important facts respecting the constitution of bodies."
30. "In the year 1808, I published my first essay on the subject of the atomic theory, in which I endeavored to prove that chemical analysis and synthesis do not enable us to go further than to the separation of particles one from another, and to their reunion."