The continental European countries that started to industrialize after 1815 had a big advantage that Great Britain had lacked, and that was that they already had the terrain set for it and the equipment was already invented.
Great Britain did the hard work, as in the process of industrialization it had to invent new things, make the machines out of scratch, be innovative constantly in order to develop it.
The countries in continental Europe though, had the dirty work done for them. They got the ready technology and they did not went to the hard process of developing it. That resulted in a very quick and effective industrialization of these countries, which led to an economic boom and significant increase in wealth.