In organic chemistry there exist certain types which are conserved even when, in place of hydrogen, equal volumes of chlorine, of bromine, etc. are introduced.

In inorganic chemistry the radicals are simple in organic chemistry they are compounds—that is the sole difference.

In chemistry, our theories are crutches to show that they are valid, they must be used to walk... A theory established with the help of twenty facts must explain thirty, and lead to the discovery of ten more.

I have seen many phases of life I have moved in imperial circles, I have been a Minister of State but if I had to live my life again, I would always remain in my laboratory, for the greatest joy of my life has been to accomplish original scientific work, and, next to that, to lecture to a set of intelligent students.