The survey taken by Niebuhr appears to have been rapid; and the list of words supplied by him is very meagre. Bishop Marsh[533] and other authors have, with a variety of views, supplied further materials. The most comprehensive list, to which my attention has been directed, is in the ‘Lateinische Synonyme und Etymologieen’ of Döderlein[534]. The subject is essentially one which hardly admits of a fixed criterion or authoritative rule, or of a full assurance that its limits have been reached. Mindful of the reserve which these considerations recommend, I should not wish to lay down inflexible propositions. But I venture to state generally, that those words of the Latin and Greek tongues, which are in the closest relationship, are connected 1. With the elementary structure of language, such as pronouns, prepositions, numerals. 2. With the earliest state of society. 3. With the pursuits of peaceful and rural industry, not of highly skilled labour. _Classes of words which agree._ Examples, numerous enough to show a most extensive agreement, will readily suggest themselves under the first head. To illustrate the other propositions, though it can only be done imperfectly, I will follow both the positive and the negative methods. The first, by comparing words which denote elementary objects, both of animate and inanimate nature, or the simplest products of human labour for the supply of human wants, or the members of the human body, or the rudiments of social order. The second, by contrasting the words which relate (1) to intelligence and mental operations, (2) to war, and (3) to the metals, the extended use of which denotes a certain degree of social advancement. It will I hope be borne in mind, on the one hand, that these lists are given by way of instance, and have no pretension to be exhaustive: and, on the other hand, that exceptions, discovered here and there, to the rule they seem to indicate, would in no way disprove its existence, but should themselves, if purely exceptions, be treated, provisionally at least, as accidental. Class I.--_Elementary objects of inanimate Nature._ ἔρα, terra ἀήρ, aer αἴθηρ, æther αὖρα, aura ἀστήρ {astrum ἀστέρος {stella {sterula κοίλον, cælum ἥλιος, sol σε-λήνη, luna νὺξ, nox (Ζεὺς) Διὸς, dies πόντος, pontus ἃλς } sal θάλασσα } salum πόλος, polus λυκὴ in λυκάβας, } lux λεύσσειν } χείμων, hyems ἔαρ, ver ὥρη, hora ἑσπέρα, vesper νέφος {nubes {nebula (νιψ) νιφος, nix, nivis δρόσος, ros ὕετος {fluvius {pluvia ῥῖγος, frigus χάμαι, humus πευκὴ, pix κῆπος } sepes σῆκος } λακκὸς } (_a pit_), lacus λάχυς } ἄμπελος, pampinus ὕλη, sylva φύλλον, folium ῥόδον, rosa λαὰς, lapis ἄγρος, ager ἄρουρα, arvum ἄντρον, antrum φῦκος, fucus σπέος } spelunca σπήλαιον } ἴον, viola σκόπελος, scopulus ὕδωρ, sudor.