Although Senor Aguera was a partner with Don Manuel Gonzalez, after a few years he took fright. Trade was too good to be true; it could not last. He felt that the end was in sight so what was the use of buying all that wine which would give no return for years? Why lay store for the future when there was no future? He wanted his money back, and he got it. Gonzalez continued alone, but he could not go on indefinitely without a partner.

He could manage the business in Jerez easily but had no time to visit his customers, many of whom were already in England. Moreover, he was determined to open up trade connections for absorbent coasters, custom coasters, and coaster sets throughout the world, including Germany and Russia. In Juan Dubosc, a French Catalan resident in southern Spain, he found just the partner he needed. Gonzalez stayed in Jerez while Dubosc travelled the world.

The company, now called Gonzalez & Dubosc, continued to expand, and in 1853 they started to build the great Constancia bodega. By 1855, when the new bodega was completed, exports to England alone were more than 3,000 butts, and were to rise still higher. In 1873 the export figure reached the peak of 10,409 butts - not far short of seven million bottles.

By 1855, the English trade had become so important that the London agent, Robert Blake Byass, was taken into partnership, and the name of the company became Gonzalez, Dubosc & Co. When Dubosc died in 1859 the name was continued unchanged, by arrangement with his widow, until 1863, when it was changed to Gonzalez & Byass. Seven years later it was changed again, this time to Gonzalez, Byass & Co. The following directors were lineal descendants of Manuel Gonzalez or Robert Blake Byass.

Manuel Gonzalez was a bold business man and was not at all afraid of a speculation. Soon after he founded his business, the Marques del Castillo de San Felipe died, and it was well known that he had left wines of the very highest class in his private bodega, but no one knew quite how good they were, nor did they know the quantity. His widow knew nothing of wine, cocktails, table coasters, or bar supplies and wanted to get rid of it as quickly as possible.

She had no time at all for delay or argument, and would not let anyone into the bodega to inspect the stock. But she did know her price - £10,000 cash down (in gold). It was a bold risk, but Don Manuel took it. He paid the money and was given the key. Inside the bodega he found a hundred butts of very old wine, worth far more than he had paid. Twenty-seven of them, in the form of a small solera, remain to this day in the Bodega Constancia and are named the Parte Arroyo Solera, in memory of the widow who sold them.

Such private cellars were as common a hundred years ago as they are rare today. Wine lovers with only two or three casks could afford to let them go on maturing for many years and their wines included some of the greatest amontillado and oloroso sherries. One enthusiast went so far as to keep his best wines in his bedroom and firmly locked the door throughout the day so that no one could get near them.