A collection of letters, in which the imperfection of learning, even among Christians, and a remedy for it, are hinted. The Usefulness of the Celtick is instanced, in illustrating the Antiquities of the British Isles, in pointing out the Errors of Mr. Innes, and the most ancient People and Language; some Elements of which are set down. The Affinity betwixt the Language of the Americans of the Terra Firma, and these of the ancient Britains, is proved. The Scripture-Account of Things is confirm'd. An Objection against Revealed Religion, heretofore not fully answered, is removed. A Specimen of a Dictionary, English-Celtick, and Celtick-English, is given. As also, a collection of papers, In which the Proceedings of the Honourable Society of Improvers, the Honourable and Learned Faculty of Advocates, some General Assemblies, their Commissions and Committees, and the Testimonies of some learned Men about this affair, are represented.