On Tuesday evening of last week (28th ult.,) Gen. John Dix delivered a most able and appropriate lecture before the Mechanics Institute of this city. The subject was, " The Influence of Government upon the Industrial Classes." Our New York Mechanics did themselves no great credit by having so many empty seats in the lecture room. Gen. Dix is one of the most chaste and clea peakers in our country. He sketched the listorythe rise and progressof the mecha-lical classes from the days of Athens' fame and iome's glory up to the present day. He ho wed the importance of our mechanics hav-ng a knowledge of law and political economy, )ut*we regret to say the intelligent few only vere there to appreciate. The mechanics in few York City are not united, their efforts ire conflicting, separate, and therefore feeble. i they were united in one thing, they could iupport one of the finest Institutes in the world.