From documents presented to Parliament, it appears, that, in 1850, there was a Christian population, in Sierra Leone, of more than 36,000, out of about 45,000. In this population, it was estimated, that there were representatives of no fewer than one hundred different tribes, speaking different languages and dialects; so that there are already converts prepared, as far as the knowledge of the languages is concerned, to go forth in every direction, and to explain to their countrymen, in their own tongue, the truths of revelation. Since the subject was before Parliament, BISHOP VIDAL has commenced his labors, and this question has received particular attention. It has been ascertained that no fewer than 151 distinct languages, besides several dialects, are spoken in Sierra Leone. They have been arranged under 26 groups; but there still remain 54 unclassified, which are more distinct from each other, and from all the rest, than the languages of Europe are from one another; thus unfolding to the view of the Christian philanthropist, an agency, in the course of preparation, which, under Divine Providence, may carry the Gospel to the unnumbered millions of immortal souls inhabiting the continent of Africa. A few facts will show that this is not an idle speculation, but that she has successfully entered upon her great mission. Among the Recaptured Africans introduced into Sierra Leone, and brought under the civilizing influences of its Christian institutions, none have made such rapid progress as the people of Yoruba, a country lying eastward of the kingdom of Dahomey. Their first appearance in the Colony was about 1822. Many of them soon acquired a considerable amount of intelligence and a little property. In 1839, they had become quite numerous, and a party of them purchased a vessel, hired a white captain, and commenced a traffic with Badagry. This town is at a point on the coast from which the Yoruba country can be most easily reached. The trade thus begun soon led to a rapid emigration from Sierra Leone, and the planting of missions at both Badagry and Abbeokuta, the capital of Yoruba.