Chemical element element (by mass) making up Earth, while oxygen is the most common element in the Earth's crust. Chemical elements constitute all of the ordinary matter of the universe. However astronomical observations suggest that ordinary observable matter makes up only about 15% of the matter in the universe: the remainder is dark matter; the composition of this is unknown, but it is not composed of chemical elements. The two lightest elements, hydrogen and helium, were mostly formed in the Big Bang and are the most common elements in the universe. The next three elements (lithium, beryllium and boron) were formed mostly
Lowest bridging point often was at a location that allowed seagoing traffic to approach it from a downstream direction. Examples of lowest bridging points in Britain include London, the lowest bridging point on the Thames; Lancaster, the lowest bridging point on the Lune; York, the lowest bridging point on the Ouse; and Gloucester, the lowest bridging point on the Severn. Glasgow grew up at the lowest bridging point on the Clyde which was about twelve miles upstream from its lowest fording point at Dumbuck. Mathew Paris’s map of 1247 appears to show only one bridge in the whole of Britain: at Stirling, the