The death of Mr. DOUGLAS has clad a nation in mourning. Stern men held their breath and clenched their hands, as the fearful intelligence reached them. It had entered into no one’s calculation that he might fall by death. In the prime of life, with vast powers of endurance,—which he so often taxed to the utmost and escaped unharmed,—it was thought he could but go on, for years; and that death would find no portcullis open, through which it could enter and slay. But what was deemed an impossibility of yesterday, has become a shocking certainty of to-day. STEPHEN A. DOUGLAS—the chivalrous, noble leader of a mighty party—lies dead in his coffin, and a nation weeps by its side!

Never, in his proudest day—with his greatest victories in the Senate or the forum—was he so considered as he is at this hour. Nought but his cold remains lie there. His eye has no speculation—his tongue silent as the voices a century agone—and yet his hold upon the heart, who believed in him as a true man, was never so firm and tenacious as to-day. No longer can he do or say aught for these millions of devoted souls—and yet, never in the plenitude of his power, when he would do all man could, was he so potential as now! Oh mighty power of human devotion! Noblest in its nobility, when its object lies helpless and lifeless before the world! Then, uprising in the might of its moral power—though its strength is gone forever—yet it rolls away the stone from every human heart that bowed to its greatness and goodness—and the waters gush forth, till the welling out of this bursting heart [reaches?] the length and breadth of the land.

How the whole scene is changed! And yet how human is the change! But a few months since—and who does not recollect the occasion—our city was thrown into that excitement seldom felt, as the rumor came to us that the great northwestern orator, the eminent statesman, the man that had risen, with no hand to help him, and no voice to cheer him, till he forced them to the work by his stupendous genius—that this noble man was on his way and would soon be here! How the eyes of his admirers flashed with pride! Now will stand up in our midst the man who has risen, despite his humble beginnings, to the noblest position in the world. The great heart of the people beat in unison with his. He was their leader, and the sympathy was perfect between them. “He came, he saw, he conquered.” His journey from Bangor to his western home was an ovation. He made thousands of converts on the way. Who does not recollect that day when he rode through our city, and spoke in the Square! It was an epoch in a life, and never to be forgotten. How the scene is changed. Then the whole country was jubilant with excitement and joy. Their ideal was realized! A man of the people, who had lived nearly a half a century, and yet continued true to the people! It was a noble contemplation—and the heart might well be excused at the pride and exultation which went up from hamlet and city, as the noble man scattered words of wisdom as he passed on his way! To-day, as we write, the sad notes of the funereal bell are making mournful melody—the minute gun is reverberating on the quivering air. The coffin-lid is open—look in and behold! It is the passive form of STEPHEN A. DOUGLAS lies within, cold in death! Well may the flag of our country trail at half-mast, for thousands of defenders in truth went down when this patriot fell asleep!

The death of Mr. Douglas is a National calamity. It cannot be measured in a day. There are some events, so appalling and full of consequences, that they cannot be grasped in a month or a year even. They develope in their fearfulness as time rolls on. This is one of them.—Years hence it will be said, very like, “if Douglas had but lived, this could not have been.” And so humanity is ever learning its lesson of unreliance.

But while we mourn, let us also rejoice. Rejoice that he lived so long, and was enabled to do so much. What a catalogue of glories crown his head. What a magnificent chaplet rests on the apex. The crowning act, superior to all the rest. Dying in the midst of his glorious efforts for the preservation of his country, a halo of glory wraps him as with a robe of sunlight! How he threw his mighty soul into the struggle which this country is now making for the integrity of its constitution and laws! How his clarion voice rang out all the way, as he journeyed along through the Northwest—its concluding notes ever being, THE UNION AND THE CONSTITUTION! Let us, we say, be thankful, while we mourn. True, a great man is dead—but equally true, that great man lived long enough to bind together as in one, the hearts of millions of men in defense of our country, in all its integrity and purity. We may weep, but not as those without hope—for the good man has not ceased till he had completed a gigantic work. Ages will not dim its lustre.