It is only to express my thanks to certain kind correspondents for the assistance they have afforded me, that I shall delay the Reader from the work now before him. To one gentleman of the highest scientific attainments and reputation I am indebted for many suggestions, of which I have availed myself in my brief view of the "State of Science." To another gentleman, qualified, perhaps, before all men living, to judge profoundly of the philosophy of Bentham, I am also indebted for considerable aid in the sketch of that remarkable writer's moral and legislative codes, which will be found in the Appendix; and to the taste and critical knowledge of a third gentleman I owe many obligations, in the chapter devoted to the survey of the "State of the Arts" amongst us at this time. To the last gentleman my acknowledgments are perhaps the greater, because he has suffered me, in his general approbation of my theories, to apply a part of his knowledge to some conclusions with which he does not wholly agree.