PRESBURG, SEPTEMBER 21st. Maria Theresa, since that fine Coronation-scene, June 28th, has had a mixed time of it with her Hungarian Diet; soft passages alternating with hard: a chivalrous people, most consciously chivalrous; but a constitutional withal, very stiff upon their Charter (PACTA CONVENTA, or whatever the name is); who wrangle much upon privileges, upon taxes, and are difficult to keep long in tune. Ten days ago (September 11th), her Majesty tried them on a new tack; summoned them to her Palace; threw herself upon their nobleness, "No allies but you in the world" (and other fine things, authentically, as above, legible in the Archives to this day):--so spake the beautiful young Queen, her eyes filling with tears as she went on, and yet a noble fire gleaming through them. Which melted the Hungarian heart a good deal; and produced fine cheering, some persons even shedding tears, and voices of "Life and Fortune to your Majesty!" being heard in it. In which humor the Diet returned to its Session-House, and voted the "Insurrection,"--or general Arming of Hungary, County by County, each according to its own contingent;--with all speed, in pursuance of her Majesty's implied desire. This was voted in rapid manner; but again, in the detail of executing, it was liable to haggles. From this day, however, matters did decidedly improve; PACTA CONVENTA, or any remainder of them, are got adjusted,--the good Queen yielding on many points. So that, September 20th, Grand-Duke Franz is elected Co-regent,--let him start from Vienna instantly, for Instalment;--and it is hoped the Insurrection will go well, and not prove haggly, or hang fire in the details. At any rate, next day, September 21st, Duke Franz, who arrived last night,--and Baby with him, or in the train of him (to the joy of Mamma!)--is in the Palace Audience-Hall, "at 8 A.M.;" ready for the Diet, and what Homagings aud mutual Oath, as new Co-regent, are necessary. Grand-Duke Franz, Mamma by his side, with the suitable functionaries; and to rearward Nurse and Baby, not so conspicuous till needed. Diet enters with the stroke of 8; solemnity proceeds. At the height of the solemnity, when Duke Franz, who is really risen now to something of a heroic mood, in these emergencies and perils, has just taken his Oath, and will have to speak a fit word or two,--the Nurse, doubtless on hint given, steps forward; holds up Baby (a fine noticing fellow, I have no doubt,--"weighed sixteen pounds avoirdupois when born"); as if Baby too, fine mutual product of the Two Co-regents, were mutually swearing and appealing. Enough to touch any heart. "Life and blood (VITAM ET SANGUINEM) for our Queen and Kingdom!" exclaims the Grand-Duke, among other things. "Yes, VITAM ET SANGUINEM!" re-echoes the Diet, "our life and our blood!" many-voiced, again and again;--and returns to its own Place of Session, once more in a fine strain of loyal emotion.