16
acting as a sorter, of admitting certain substances and preventing the
passage of others, and consequently of separating the elements of cer-
tain combinations in order to admit only a portion of them.”
6
Raspail
was thus the first person to systematically investigate the chemistry
of a cell. He also noted how disease originates in the basic cell and
spreads through cell division, a fundamental point in cell pathology.
The main flaw in Raspail’s work was his continued belief in the old
The Globule Error
Before cell theory took shape in the late 1830s, several in uential sci-
entists thought all living things were made of globules, or tiny globe-like
particles. In 1823 French scientist Henri Milne-Edwards proposed the
best-known statement of globule theory in his master’s degree thesis.
Building on the work of earlier scientists, Milne-Edwards had examined a
variety of animal organs from many species. He concluded they all con-
sisted of minute globules, about 1/300 of a millimeter in diameter. English
scientist Everard Home agreed with the globule hypothesis. Once skepti-
cal about the ability of microscopes to show clearly the details of animal
tissue, Home came to believe that improved instruments revealed glob-
ules in blood and tissues of the nerves and brain. Home’s 1823 lectures
on anatomy at the College of Surgeons in London helped spread his own
ideas about globules.
However, Joseph Lister’s invention of the achromatic microscope in
the late 1820s exploded the globule theory. The new microscope featured
lenses that produced higher magni cation with less distortion. Lister and
his associate Thomas Hodgkin observed that what looked like globules
through the old microscope lenses were actually optical illusions. As
science historian John Baker writes, “The fact that the excesses of the
globulists were exposed by Lister’s microscope seems signi cant; for the
particular advantage of his instrument was that spherical aberration was
corrected and the ‘ring’ appearance round small particles thus reduced.”
As a result a better microscope led scientists closer to the truth about cells.
Quoted in Giora Hon, Jutta Schickore, and Friedrich Steinle, eds.,
Going Amiss in Experimental
Research
. New York: Springer, 2009, p. 29.
