The contrast in scientific activity between 1818 and 1918 is nowhere more strikingly shown than in the amount of scientific periodical literature of the two periods. Of the thousands of scientific journals and regular publications by scientific societies and academies to-day, but a very small number have carried on a continuous and practically unbroken existence since 1818. This small amount of periodical scientific literature in the early part of the last century is significant as giving a fair indication of the very limited extent to which scientific investigation appealed to the intellectual life of the time. Some definite facts in regard to the scientific publications of those early days seem to be called for. Learned societies and academies, devoted to literature and science, were formed very early but at first for occasional meetings only and regular publications were in most cases not begun till a very much later date. Some of the earliest—not to go back of the Renaissance—are the following: 1560. Naples, Academia Secretorum Naturæ. 1603. Rome, Accademia dei Lincei. 1651. Leipzig, Academia Naturæ Curiosum. 1657. Florence, Accademia del Cimento. 1662. London, Royal Society. 1666. Paris, Académie des Sciences. 1690. Bologna, Accademia delle Scienze. 1700. Berlin, Societas Regia Scientiarum. This was the forerunner of the K. preuss. Akad. d. Wissenschaften. The Royal Society of London, whose existence dates from 1645, though not definitely chartered until 1662, began the publication of its “Philosophical Transactions” in 1665 and has continued it practically unbroken to the present time; this is a unique record. Following this, other early—but in most cases not continuous—publications were those of Paris (1699); Berlin (1710); Upsala (1720); Petrograd, 1728; Stockholm (1739); and Copenhagen (1743). For the latter half of the eighteenth century, when the foundations of our modern science were being rapidly laid, a considerable list might be given of early publications of similar scientific bodies. Some of the prominent ones are: Göttingen (1750), Munich (1759), Brussels (1769), Prague (1775), Turin (1784), Dublin (1788), etc. The early years of the nineteenth century saw the beginnings of many others, particularly in northern Italy. It is to be noted that, as stated, only rarely were the publications of these learned societies even approximately continuous. In the majority of cases the issue of transactions or proceedings was highly irregular and often interrupted. In this country the earliest scientific bodies are the following: Philadelphia. American Philosophical Society, founded in 1743. Transactions were published 1771–1809; then interrupted until 1818 _et seq._ Boston. American Academy of Arts and Sciences, founded in 1780. Memoirs, 1785–1821; and then 1833 _et seq._