"This is connected with another question, the source from which the ancient world was supplied with the prodigious quantity of bronze arms and utensils which we know to have existed. This caught my imagination many years since, and I then analyzed a great variety of bronzes, with such uniform results that I supposed this identity of composition was evidence of their all coming from the same manufactures. Afterwards I found that the peculiar properties of the atomic compound already referred to are sufficiently distinct to make any metallurgist who was engaged in such a manufacture select it. It also appears to me more permanent in the crucible." Dr. Robinson states that this alloy, when used for weapons, is a constant chemical compound containing fourteen equivalents of copper and one of tin, or nearly eighty-eight parts of the former and twelve of the latter by weight. But no account is given by him of the process of analysis, and the results justify the supposition that in these experiments, as in those of Dr. Clarke of Cambridge, he had assumed the absence of all other metals, and sought only for copper and tin.[287] Notwithstanding the opinions quoted above, Dr. Robinson still inclines, on other grounds, to the conclusion that we are justified in tracing the bronze to some common source, and this he conceives to be the Phœnicians. In all the weapons and implements the points are entire and sharp, and the edges unbroken. The spear-heads are the most remarkable as specimens of workmanship. They are of various sizes, and of great diversity of pattern, and also have their points and edges perfect as if they had never been used. They prove, as Dr. Robinson remarks, not only that the workmen who made them were masters of the art of casting, but also that they possessed high mechanical perceptions; their productions shewing a skilful adaptation of the material to the end in view. These indications appear to him to confirm the idea of their derivation from some foreign source. "Yet," he also adds, "in many of them the colour of the bronze is such as, at first sight, to excite a suspicion that they were gilded." This has already been noted as a peculiarity observed hitherto almost exclusively in the primitive bronze relics of Scotland and Ireland, and even there occurring in greatest abundance in certain districts. Dr. Petrie observed, at the meeting of the Academy, that all the bronze relics found in King's County have the characteristic golden tinge referred to, and added that the number of beautiful moulds for hatchets and other implements of warfare found from time to time in Ireland, prove that the ancient Irish understood the art of manufacturing bronze instruments such as those discovered in the vessel found at Dooros Heath.