Our morning report of that morning made our effective men present fit for duty 1060, without including the detachment before alluded to, and without including 300 of the Michigan militia on duty. About dark on Sunday evening the detachment sent to escort the provisions received orders from General Hull to return with as much expedition as possible. About ten o'clock the next day they arrived within sight of Detroit. Had a firing been heard, or any resistance visible, they would have immediately advanced and attacked the rear of the enemy. The situation in which this detachment was placed, although the result of accident, was the best for annoying the enemy and cutting off his retreat that could have been selected. With his raw troops enclosed between two fires and no hopes of succor, it is hazarding little to say, that very few would have escaped.

I have been informed by Colonel Findley, who saw the return of the quarter master general the day after the surrender, that their whole force of every description, white, red and black, was 1030. They had twenty-nine platoons, twelve in a platoon, of men dressed in uniform. Many of these were evidently Canadian militia. The rest of their militia increased their white force to about seven hundred men.

The number of their Indians could not be ascertained with any degree of precision; not many were visible. And in the event of an attack upon the town and fort, it was a species of force which could have afforded no material advantage to the enemy.

In endeavoring to appreciate the motives and to investigate the causes which led to an event so unexpected and dishonorable, it is impossible to find any solution in the relative strength of the contending parties, or in the measures of resistance in our power. That we were far superior to the enemy; that upon any ordinary principles of calculation, we could have defeated them, the wounded and indignant feelings of every man there will testify.

A few days before the surrender, I was informed by General Hull, we had 400 rounds of 24 pound shot fixed, and about 100,000 cartridges made. We surrendered with the fort 40 barrels of powder and 2500 stand of arms.

The state of our provisions has not been generally understood. On the day of the surrender we had fifteen days of provisions of every kind on hand. Of meat there was plenty in the country, and arrangements had been made for purchasing and grinding the flour. It was calculated we could readily procure three months' provisions, independent of 150 barrels of flour, and 1300 head of cattle which had been forwarded from the state of Ohio, which remained at the river Raisin under Captain Brush, within reach of the army.

But had we been totally destitute of provisions, our duty and our interest undoubtedly was to fight. The enemy invited us to meet him in the field.

By defeating him the whole country would have been open to us, and the object of our expedition gloriously and successfully obtained. If we had been defeated we had nothing to do but to retreat to the fort, and make the best defense which circumstances and our situation rendered practicable. But basely to surrender without firing a gun tamely to submit without raising a bayonet disgracefully to pass in review before an enemy as inferior in the quality as in the number of his forces, were circumstances, which excited feelings of indignation more easily felt than described. To see the whole of our men flushed with the hope of victory, eagerly awaiting the approaching contest; to see them afterwards dispirited, hopeless and desponding, at least 500 shedding tears, because they were not allowed to meet their country's foe, and to fight their country's battles, excited sensations, which no American has ever before had cause to feel, and which, I trust in God, will never again be felt, while one man remains to defend the standard of the union.

I am expressly authorized to state, that Colonel McArthur and Colonel Findley, and Lieutenant Colonel Miller, view this transaction in the light which I do. They know and feel, that no circumstance in our situation, none in that of the enemy, can excuse a capitulation so dishonorable and unjustifiable. This too is the universal sentiment among the troops; and I shall be surprised to learn, that there is one man, who thinks it was necessary to sheath his sword, or lay down his musket.

I was informed by general Hull the morning after the capitulation, that the British forces consisted of 1800 regulars, and that he surrendered to prevent the effusion of human blood. That he magnified their regular force nearly five fold, there can be no doubt. Whether the philanthropic reason assigned by him is a sufficient justification for surrendering a fortified town, an army and a territory, is for the government to determine. Confident I am, that had the courage and conduct of the general been equal to the spirit and zeal of the troops, the event would have been as brilliant and successful as it now is disastrous and dishonorable.

I have the honor to be yours, &c.,

LEWIS CASS.