Thus we see that the period during which the number of alien laborers in the United States was decreasing was confined to the months December, 1907, to August, 1908, inclusive.[319] By the end of July, 1908, the effects of the crisis were practically over as far as departures are concerned. It is evident, then, that the effects of the crisis on emigration were immediate, but not of very long duration. During the months of November and December, 1907, when the distress was the keenest, there were still large numbers of aliens arriving. But when the stream of immigration was once checked, it remained low for some time, and it was not until about January, 1909, that it returned to what may be considered a normal figure. The reasons for this are obvious. The stream of immigration is a long one, and its sources are remote. It takes a long time for retarding influences in America to be thoroughly felt on the other side. The principal agency in checking immigration at its source is the returning immigrant himself, who brings personal information of the unfortunate conditions in the United States. This takes some time. But when the potential immigrants are once discouraged as to the outlook across the ocean, they require some positive assurance of better times before they will start out again. Now what catches the public eye in such an epoch as this is the large number of departures. We are accustomed to immense numbers of arrivals and we think little about that side of it. But heavy emigration is a phenomenon, and accordingly we hear much about how acceptably our alien population serves to accommodate the supply of labor to the demand. But if we stop to add up the monthly figures, we find that for the entire period after the crisis of 1907, when emigration exceeded immigration, the total decrease in alien population was only 124,124—scarcely equal to the immigration of a single month during a fairly busy season. This figure is almost infinitesimal compared to the total mass of the American working people, or to the amount of unemployment at a normal time, to say nothing of a crisis.[320] It is thus evident that the importance of our alien population as an alleviating force at the time of a crisis has been vastly exaggerated. The most that can be said for it is that it has a very trifling palliative effect.