The soft paste of Sèvres, even during the period of the fifties and sixties, when the most exquisite ware was being made, seems always to have been regarded somewhat as a make-shift, to be employed until the materials for making a true porcelain should be discovered in France. For it was the ignorance of the true nature of kaolin, and where to look for it, that so fortunately delayed its introduction at Sèvres. As early as the Vincennes days, one of the Hannongs of Strassburg had offered to sell his secret, and this offer was repeated at a later time by himself and by his son. At Sèvres, before 1760, two German workmen were retained to teach the Saxon process, but the materials had still to be obtained from Germany. Meantime Macquer, who had succeeded to the post of scientific adviser on the death of Hellot, had been experimenting on his own account, and above all encouraging others to search for the precious white earth within French territory. At length, in 1760, some samples were sent from Alençon, from which a true porcelain was made, but of poor quality and of a grey colour. Outside the Sèvres works the younger Hannong had set up a factory at Vincennes, and the Comte de Brancas Lauraguais, whom we shall meet with again in England, had by 1764 begun his experiments and his search after deposits of kaolin. There still exist a few portrait-medallions moulded in hard porcelain, which, on the ground of the letters B. L. engraved on the back, have been attributed to that energetic nobleman. The introduction, however, of the hard-paste porcelain at Sèvres dates from the discovery, in 1768, at Saint-Yrieix, near Limoges, of those famous deposits of kaolin which have ever since that time been the main resource of the French porcelain industry.[194] Before the end of the year 1769 Macquer was able to show to the king the first samples of this new ware. The hard paste made for some years after this date was not of the ‘severe’ type adopted later on. Not only did it contain as much as 9 per cent. of lime, but, the kaolin employed being less pure, contained probably a good deal of mica--in fact, this first type of French hard paste approached in composition that of the Chinese. It is even more important to note that the glaze used at the same time was of an entirely different nature from the pure felspathic covering afterwards adopted. It was composed of Fontainebleau sand 40 per cent., potsherds of hard porcelain 48 per cent., and chalk 12 per cent. As a result, it was possible to decorate the surface with brilliant translucent enamels of some thickness.