The most influential Purâṇa is the Bhâgavata, one of the great scriptures for all sects which worship Kṛishṇa. It is said to have been translated into every language of India and forty versions in Bengali alone are mentioned.[446] It was probably composed in the eighth or ninth century.[447] A free translation of the tenth book into Hindi, called the Prem Sagar or Ocean of Love, is greatly revered in northern India.[448] Other sectarian Purâṇas are frequently read at temple services. Besides the eighteen great Purâṇas there are many others, and in south India at any rate they were sometimes composed in the vernacular, as for instance the Periya Purâṇa (_c._ 1100 A.D.). These vernacular Purâṇas seem to be collections of strangely fantastic fairy tales. C. The word Tantra originally meant a manual giving the essentials of a subject but later usage tends to restrict it to works, whether Hindu or Buddhist, inculcating the worship of Śiva's spouse. But there are exceptions to this restriction: the Panca-tantra is a collection of stories and the Lakshmî-tantra is a Vishnuite work.[449] The fact is that a whole class of Sanskrit religious literature is described by the titles Tantra, Âgama and Saṃhitâ,[450] which taken in a wide sense are practically synonymous, though usage is inclined to apply the first specially to Śâktist works, the second to Śivaite and the third to Vishnuite. The common character of all these productions is that they do not attempt to combine Vedic rites and ideas with sectarian worship, but boldly state that, since the prescriptions of the Veda are too hard for this age, some generous deity has revealed an easier teaching. This teaching naturally varies in detail, but it usually comprises devotion to some special form of the godhead and also a special ceremonial, which commences with initiation and includes the use of mystic formulæ, letters and diagrams. Tantras, Âgamas and Saṃhitâs all treat of their subject-matter in four divisions[451] the first of which relates to the great problems of philosophy, the second to the discipline necessary for uniting the self and God; the third and fourth to ceremonial.