at the same time to other matters.  He was already pondering the structure of the great African Continent, and carefully investigating the process of desiccation that had been going on for a long time, and had left much uncomfortable evidence of its activity in many parts.  In the desert, he informs his friend Watt that no fewer than thirty-two edible roots and forty-three fruits grew without cultivation.  He had the rare faculty of directing his mind at the full stretch of its power to one great object, and yet, apparently without effort, giving minute and most careful attention to many other matters,—­all bearing, however, on the same great end.

A very interesting letter to Dr. Risdon Bennett, dated Kuruman, 18th December, 1841, gives an account of his first year’s work from the medical and scientific point of view.  First, he gives an amusing picture of the Bechuana chiefs, and then some details of his medical practice: 

The people are all under the feudal system of government, the chieftainship is hereditary, and although the chief is usually the greatest ass, and the most insignificant of the tribe in appearance, the people pay a deference to him which is truly astonishing....  I feel the benefit often of your instructions, and of those I got through your kindness.  Here I have an immense practice.  I have patients now under treatment who have walked 130 miles for my advice; and when these go home, others will come for the same purpose.  This is the country for a medical man if he wants a large practice, but he must leave fees out of the question!  The Bechuanas have a great deal more disease than I expected to find among a savage nation; but little else can be expected, for they are nearly naked, and endure the scorching heat of the day and the chills of the night in that condition.  Add to this that they are absolutely omnivorous.  Indigestion, rheumatism, opthalmia are the prevailing diseases....  Many very bad cases were brought to me, sometimes, when traveling, my wagon was quite besieged by their blind and halt and lame.  What a mighty effect would be produced if one of the seventy disciples were among them to heal them all by a word!  The Bechuanas resort to the Bushmen and the poor people that live in the desert for doctors.  The fact of my dealing in that line a little is so strange, and now my fame has spread far and wide.  But if one of Christ’s apostles were here, I should think he would be very soon known all over the continent to Abyssinia.  The great deal of work I have had to do in attending to the sick has proved beneficial to me, for they make me speak the language perpetually, and if I were inclined to be lazy in learning it, they would prevent me indulging the propensity.  And they are excellent patients, too, besides.  There is no wincing; everything prescribed is done instanter.  Their only failing is that they become tired of a long course.  But in any operation, even the women sit unmoved.  I have been quite astonished