The First Annual Report of Commissioner Holt, as it appeared in the SCIENTIFIC AMERICAN, three weeks since, has gained for him an unusual degree of approbation from inventors and patentees generally ; and with but a single exception, it has received unqualified praise from the press. The exception referred to was an ill-mannered, ignorant, personal assault, in the shape of a communication through the columns of one of our daily papers, upon the motives of the Commissioner. We are well satisfied that the editor would never have admitted its publication, had he carefully perused the Commissioner's report. We think we could point out the author without much labored guessing. He had evidently suffered personal inconvenience at the hands of the new Commissioner, who has naturally been desirous to distinguish his friends from his enemies. The criticism was conceived in bad taste, was unfair in every respect, and exhibited a malice characteristic of that opposition which has attempted to lift its puny head above the Commissioner's rightful authority, for the purpose of interposing obstacles to the introduction of a policy more in accordance with the spirit of the law. As an evidence, showing the good feeling elicited by this report, we would mention the case of an aged inventor, from a neighboring State, who called upon us a few days since, and expressed his warm commendation of the report. He remarked, with much emphasis, that " it was something new for a Commissioner to espouse, and plead so eloquently for, the cause of the inventor ;" instancing, at the same time, the repulsive spirit with which he had been received at the Office on some former occasions. He also referred to the fact that he had now in his possession Letters Patent issued ip 1807, and signed (as was then customary) by President Jefferson, and others subsequently signed by Madison, Monroe, and Jackson—those venerable worthies of other days. We believe our friend to be one of the oldest living inventors. He began to take out patents under the administration of Jefferson, has done so under nearly every succeeding administration, and, if we mistake not, he has claims now pending before the Patent Office. The commendation of one such inventor will compensate for the sullen growls and feeble kicks of a score of those who find their toes trodden upon and their selfish schemes frustrated by an independent and fearless Commissioner, who is evidently determined to administer the affairs of the Patent Office so as to commend it to the sympathy and favor of all just men. The Office now occupies a much higher position in public estimation than at any previous period in its history. While other departments of the government appear to be suffering from the fearful pressure of the times, this alone shows signs of healthy progress. Why is this ? In solving this query, we need not summon to our aid the Delphian gods, or " the spirits in the vasty deep." Nor need we heed the gloomy forebodings of those whose dirty intrigues have been frustrated. The Commissioner's just and humane policy is vindicating itself, and its fruits form an index finger to a solution of the cause of the present anomalous prosperity of the Patent Office.