Leonardo's Wood Charring Method Predates Japanese Practice In the world of sustainable architecture and construction, a centuries-old Japanese technique known as "yakisugi" has gained significant attention in recent years. Yakisugi involves charring the surface of wood, creating a carbonized layer that protects the material from water, fire, insects, and fungi, thereby extending its lifespan. While this practice was first formally documented in Japan during the 17th and 18th centuries, new research suggests that the Italian Renaissance polymath Leonardo da Vinci had discovered the benefits of wood charring over a century earlier. The discovery, published in the open-access repository Zenodo, sheds light on the remarkable foresight and breadth of Leonardo's scientific investigations. Throughout his prolific career, the legendary artist, inventor, and scholar produced more than 13,000 pages of notebooks, a substantial portion of which has survived to the present day. These notebooks contain an astonishing array of ideas and inventions, many of which foreshadowed future technological advancements. Among the numerous areas of Leonardo's expertise was his understanding of the natural world and the properties of materials. It was during his explorations of these subjects that he stumbled upon the potential benefits of charring wood surfaces, a practice that would later become known as the Japanese technique of yakisugi. Leonardo's insights into the protective qualities of charred wood were documented in his notebooks, predating the formal codification of yakisugi by more than a century. This discovery not only underscores the breadth of Leonardo's scientific interests but also highlights his pioneering role in understanding the practical applications of this wood preservation method. The implications of this finding extend beyond the realms of architectural history and material science. It serves as a testament to the enduring relevance of Leonardo's work and the timeless nature of his scientific inquiries. By uncovering these early observations on wood charring, researchers have shed new light on the interconnected nature of global knowledge, showcasing how ideas can transcend cultural and temporal boundaries. Furthermore, the discovery of Leonardo's wood charring method provides an intriguing perspective on the evolution of sustainable building practices. Yakisugi, which has become increasingly popular in the field of bioarchitecture, is now recognized as a centuries-old technique with deep roots in the Renaissance period. This knowledge can inform and inspire contemporary architects and designers, encouraging them to explore historical precedents and draw inspiration from the insights of the past. The significance of this finding is not limited to the world of architecture and construction. Leonardo's notebooks have long been a source of fascination for scholars across various disciplines, as they offer a glimpse into the mind of a true Renaissance polymath. The discovery of his work on wood charring adds yet another layer to the rich tapestry of Leonardo's scientific explorations, further cementing his reputation as a visionary thinker who was ahead of his time. In addition to his observations on wood charring, Leonardo's notebooks have revealed a remarkable array of other inventions and ideas that foreshadowed future technological advancements. From the design of flying machines and bicycles to the concept of a double-hulled unsinkable ship, Leonardo's notebooks serve as a testament to his boundless creativity and his ability to envision the possibilities of the future. The rediscovery of Leonardo's work on wood charring is particularly significant in light of the growing global emphasis on sustainability and environmentally conscious design. As the world grapples with the challenges of climate change and the need for more eco-friendly construction practices, the insights provided by Leonardo's centuries-old research can offer valuable guidance and inspiration. By understanding the historical context and the significance of Leonardo's work, contemporary architects, engineers, and material scientists can build upon his foundations, exploring new and innovative ways to incorporate sustainable building techniques into their practices. The discovery of Leonardo's wood charring method serves as a powerful reminder of the enduring value of interdisciplinary collaboration and the importance of preserving and studying the intellectual legacy of the past. In conclusion, the revelation that Leonardo da Vinci's observations on wood charring predate the formal codification of the Japanese yakisugi technique is a remarkable discovery that underscores the breadth and depth of the Renaissance polymath's scientific pursuits. This finding not only sheds new light on the history of sustainable building practices but also highlights the timeless relevance of Leonardo's work and the continued importance of exploring the interconnected nature of global knowledge. As architects, designers, and material scientists continue to grapple with the challenges of sustainable construction, the insights provided by Leonardo's pioneering research can serve as a valuable resource and inspiration for the future.