Compelled to sleep on the damp ground...

Compelled to sleep on the damp ground month after month, exposed to drenching showers, and getting the lower extremities wetted two or three times every day, living on native food (with the exception of sugarless coffee, during the journey to the north and the latter half of the return journey), and that food the manioc roots and meal, which contain so much un-combined starch that the eyes become affected (as in the case of animals fed for experiment on pure gluten or starch), and being exposed during many hours each day in comparative inaction to the direct rays of the sun, the thermometer standing above 96 Deg. in the shade—these constitute a more pitiful hygiene than any missionaries who may follow will ever have to endure. I do not mention these privations as if I considered them to be "sacrifices", for I think that the word ought never to be applied to any thing we can do for Him who came down from heaven and died for us; but I suppose it is necessary to notice them, in order that no un-favourable opinion may be formed from my experience as to what that of others might be, if less exposed to the vicissitudes of the weather and change of diet.

Missionary Travels and Researches in South Africa, by David Livingstone, chapter 25.