But while thus preparing for his task, Park was not oblivious to what was more immediately around. We get glimpses of him making natural history collections by day, and taking astronomical observations by night. In particular he occupied himself in getting up the details of the trade of the Gambia. Since the time when Stibbs had ascended the river in the vain hope of reaching the Niger, a considerable change had come over the commerce of the region. The fancied wealth of Timbuktu had not been tapped, but the commodities of the countries within reach of the river had proved no inconsiderable source of profit. In the year 1730 we find one factory alone consisting of a governor, deputy-governor, and two other principal officers; eight factors (hence the word factory) or trading agents, thirteen writers, twenty inferior attendants and tradesmen, a company of soldiers, and thirty-two negro servants, not to speak of the crews of various sloops, shallops, and boats. From that date, however, competition set in, till at the end of the century the gross value of British exports had fallen to £20,000. It is worthy of note that even in Park’s time the chief article of export is slaves. Accustomed as we are in these days to denounce in the strongest terms this vile traffic, and to brand as the most degraded and brutal of their race those who engage in it, it is difficult to realise that less than a century ago we ourselves were the chief traffickers in human flesh and blood. How little this horrible trade touched the conscience of the individual or of the country at large is sufficiently shown by Park’s own narrative. We seek there in vain for a word of condemnation, or the indication of a consciousness that there was any iniquity in it. Not, be it noted, for lack of knowledge of the attendant cruelties or even through lack of pity for the victims. On the contrary, he describes “the poor wretches while waiting shipment kept constantly fettered two and two together, and employed in the labours of the field; and, I am sorry to add, very scantily fed, as well as harshly treated.” Later on he accompanied a slave caravan on its way to the coast. With simple naturalness he tells the whole story of the horrors of the route, describing the fetters and chains, the frightful marches, with heavy loads, under a sweltering sun, and with starvation rations; the whip mercilessly applied to the weary to stimulate them to further exertions, and the knife placed to the throat of the hopelessly exhausted, at once to rid them of pain and their drivers of a burden--“an operation I did not wish to see, and therefore marched on.”