The last number of tho Newburyport Herald contains a letter from Hon. Robert Cross, of Marshal!, Michigan, formerly a resident in Amesbury, giving a detailed account of an unsuccessful attempt to recapture a family of fugitive slaves in that place. It seems that the family, consisting of a man, his wife, and four children, had lived in the village for about three years, and had a fair reputation for industry and sobriety. Four "hunters of Kentucky," headed by a lawyer belonging to Carroll country, in that State attempted to break into the house of the fugitive family; whereupon, an alarm was mounted on a horse, and sent through the town, ringing a bell, and calling on the people to come to the rescue of the family ; and, in a brief space of time, the people were assembled to the number of several hundreds. The correspondent of the Herald, who was on the spot, says: " The best-looking of the assailant party, who, as it afterward appeared, was a lawyer by profession, and the grandson of the alleged owner of the family, stood in the midst of the throng. What he said was delivered in courteous and conciliatory terms but it did not secure the acquiescence of his auditors.' Fellow citizens,' said one of the multitude, and he was one whose word would be taken for thousands, 'I move, as the sense of this meeting, that Crosswhite is a citizen of a free State, and, as such, must not be molested without our consent.' 'Av,' was the prompt reply. 'I also,' said the stranger, 'crave leave to submit a motion, and it is this: that the law of the land, whatever it is, be allowed to go into operation, without obstruction or confusion.' ' No,' was the loud whoop with which the proposal was answered. 'I move,' said another citizen, older than him who spoke first, and quite as high in public estimation, 'that, however the law may run, these gentlemen be made to understand, that we shall not allow one of our members to be carried away, by any person or persons, against his consent." 'Ay,' was again the prompt shout of concurrence.

In the mean time, Crosswhite, the fugitive, had obtained a warrant against the assailants for breaking open his door; and another colored man, Hackett, for an assault made upon him by the Kentuckians, with Bowie knives and revolving pistols. The Justice decided, that in Michigan every man was presumed to be free; and that his house was his unassailable castle, and therefore fined the defendants one hundred dollars and costs. They were also adjudged guilty on the complaint for assault, and compelled to recognise for their appearance at the circuit court. Alter making provision for the indemnification of their sponsors, they mounted their horses, thankful for their escape from imprisonment, and moved off southerly, making no secret of their determination never to enter the State again on a similar errand. The correspondent of the Herald, an able lawyer, and who, while n resident of Massaehusetts, was regarded as decidedly hostile to the antislavery party, says: ' The sympathy for the Crosswhites was universal, running through Whigs and Democrats, Yankees and Irish."

"This conflict between the sentiment of freedom and the law of the land was direct and palpable, unobstructed by the interposition of a single pretence circumstance. The family were undoubtedly the slaves of the claimant. The wife had been the nurse of the younger of the party; he addressed her as an old familiar, and called her 'mother.' Crosswhite did not pretend that he had ever been manumitted, or that his escape from his master was in any way known or consented to. Nor was there any mistake as to the law; for, at the outset of the matter, no less than half a dozen lawyers were present, and stated the substance of it repeatedly. Nevertheless, in the minds of the people, there seemed no doubt as to the course which they determined to pursue. Clergymen, lawyers, doctors, men of substance and men without a dollar, seemed to accord in opinion, that the law of nature was of more binding efficacy than the statute of the Union.

"After the close of the judicial inquiry, the lawyer of the party expressed a wish to address the audience, and not the least extraordinary of these proceedings were his remarks, considering the position in which he stood. He avowed himself to be hostile to the system of slavery; claimed sympathy for its burdens and inconveniences; expressed a hope that it might soon be extirpated from Kentucky; and urged, as an apology for its continuance, that it was the work of their forefathers, and not the present generation.-- l know not, if similar feelings would have been exhibited by our people a year ago." --National Era.