In the course of my memoir I have endeavoured to do justice to Holland, esteeming it to be the most remarkable country in the world. I cannot find in the history of any other nation proofs so clear of the beneficial effects of indomitable industry, directed by intelligence, over the welfare and destinies of a people; nowhere do I find evidence so convincing of the great results flowing from the application of practical science to the wants of a people; nowhere do I find to the same extent a sound commercial and political economy, first developed and acted on in Holland, lead so directly to the civilization and welfare of a nation. Those great principles which other nations and other races discussed theoretically and elaborated into systems, the nation of which you are a distinguished citizen, discovered, adopted, applied, and enforced. To Holland, as a nation, belongs eminently the character of practical. Whilst other nations left uncultivated as they found them, or rendered unproductive, the most fertile territories, seemingly unable to turn them to account, the country and people to which you belong compelled the ocean to retire from a barren, unprofitable, and untillable soil, which they converted into a garden; and if ever the great problem of rendering the whole earth habitable for man be solved, I may venture to predict--with all due respect for other nations and other races--that the solution must come from Holland. As it would be presumptuous in me--a humble individual--directly to address a nation, I have ventured to do so indirectly through you. Permit me, therefore, to dedicate this little work to you, as the expression of my personal regard and friendship, and of my deep respect for the nation to which you belong. I am, SIR, Most respectfully yours, THE AUTHOR. TABLE OF CONTENTS. INTRODUCTION. Epidemics--Their mysterious character--Distinction between endemics and epidemics--Malaria, where chiefly met with--Is it of one kind or several?--Author’s long residence in a _malaria_-producing country pp. 1–3 CHAPTER I. The question as to there being several kinds of malaria, further examined--Theory of Macculloch, tracing to a malaria, chiefly generated by man himself, all forms of disease, from the plague to a common neuralgia--This theory now accepted, and to a certain extent acted on by the British Government--Experiments of the Board of Health--Results to be seen at Luton, Birmingham, and London pp. 4, 5 CHAPTER II.