against you the next, and when contrary winds contend with a strong current, it is attended with considerable inconvenience, and requires careful and circumspect management, or you may be driven on shore in spite of all your efforts. One favourable circumstance is, that the wind commonly abates about sunset, particularly in summer.
"Boats have frequently passed from Pittsburgh to the mouth of Ohio in 15 days, but in general 10 days from Pittsburgh to the falls is reckoned a quick passsage.
"Descending the river when much incommoded with floating ice, should be as much as possible avoided, particularly early in the winter, as there is a great probability of its stopping your boat; however, if the water is high, and there is an appearance of open weather, you may venture with some propriety, if the cakes are not so heavy as to impede your progress, or injure your timbers; the boat will in such case, make more way than the ice, a great deal of which will sink and get thinner as it progresses, but on the other hand, if the water is low, it is by no means safe to em-
