 Although this met with moderate success, the outbreak of war with France, taxes and transportation costs limited the development of the quarry.A new business partnership led by Assheton Smith was formed on the expiry of the lease in 1809 and the business boomed after the construction of a horse-drawn tramway to Port Dinorwic in 1824.At its peak in the late 19th century, "when it was producing an annual outcome of 100,000 tonnes", Dinorwic employed more than 3,000 men and was the second largest opencast slate producer in the country.