Who developed a new technique for road construction, leading to improved transportation efficiency?

The individual recognized for developing a new technique for road construction is John Loudon McAdam. In the early 19th century, he introduced a method that involved laying stones in a specific way, which created a smoother and more durable road surface. This technique, known as "Macadamization," used small, crushed stones that were compacted to allow for drainage and stability, significantly enhancing transportation efficiency compared to earlier roads that were often muddy and uneven. McAdam's innovations facilitated the growth of the roadway network and improved the movement of goods and people, thereby contributing to the rapid expansion of commerce during the Industrial Revolution.

Other figures mentioned have made significant contributions in their respective fields: Isambard Kingdom Brunel is renowned for his work in railway and bridge engineering; George Stephenson is celebrated as a pioneer of steam locomotive design; and James Watt is known for his improvements to the steam engine. While their contributions were crucial to the Industrial Revolution, they did not specifically focus on road construction techniques like McAdam did.