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 which form the compounds, and are termed molecules. The molecule of a compound contains different atoms, whereas the molecule of an element contains the same atoms.

Although not an accurate manipulator (who could be with such crude apparatus at his disposal?), he was a philosopher, a deep thinker, yea, a genius. He was gifted with that most useful "article"—scientific imagination. "He formed clear mental images of the phenomena which he studied, and these images he was able to combine and modify so that there resulted a new image containing in itself all the essential parts of each separate picture which he had previously formed."

In 1837 his health began to fail and his mental powers to decline; he had a paralytic seizure, but afterwards recovered to a certain extent.

Seven years later he had another attack, which proved fatal on 27th July 1844. With public honours his remains were buried in Ardwick Cemetery, Manchester; and a massive tomb of red granite marks the spot where the founder of the atomic theory lies buried.

Of posthumous honours, there is a beautiful statue of Dalton by Sir Francis L. Chantrey in the vestibule of the Manchester Town Hall; and in the same building