LONDON:
SAVILL AND EDWARDS, PRINTERS, CHANDOS STREET,
COVENT GARDEN.
TO
M. ROCHUSSEN,
MINISTER OF COLONIES AT THE HAGUE.
Sir,—
I have taken the liberty of dedicating this little work to you. It treats of a subject on which I have made many experiments and collected many observations in Belgium and in Holland. I have carefully weighed the conflicting evidence of some distinguished observers, and the conclusion arrived at is, that this conflict has arisen partly from a want of due care in making the observations, partly from the extreme difficulty accompanying all inquiries in which physiology and pathology, health and disease, are necessarily involved.