A Concise History of the Double Yellow Line

When carriages were first used on a large scale in urban areas, the speed of the vehicles combine with the lack of paved surfaces meant that there was no delineation between lanes of traffic in cities. When cars first appeared on the streets, the significant increase in speed of vehicles resulted in an increased amount of serious collisions.

In 1907 in Birmingham, England the local lamp lighter, Thomas Freemont's son was paralyzed in a tragic automobile/carriage accident. The automobile was driving on the incorrect side of the road while attempting to pass a carriage and did not see another oncoming carriage, resulting in a serious collision. After this event, Mr. Freemont began drawing a single yellow chalk line down the center of the road in areas where there was insufficient line of site for passing thus creating a physical division of lanes in these areas.

This practice soon caught on, beginning in neighboring villages, and by 1910, lamplighters in all of central England began to get paid to draw chalk lines in treacherous areas during the day. The summer of 1911 was one of the wettest on record in central England and, as a result, the lines needed to be redrawn daily, not only an inconvenience but an increasing expense for many of the small villages. The rain, not only washed away the chalk lines, but it also resulted in massive potholes and erosion. These two factors were the impetus that began the massive effort to pave roads in cities. Once roads were paved, a single white painted line replaced the chalk markings.

As automobiles began appearing in larger numbers, another problem began presenting itself. Many of the city streets were so narrow that it was common for mirrors on two passing cars to collide and cause damage. In the spring of 1913, Frederick Holmes¹, the Minister of Agriculture, had his mirror knocked off in a minor collision. A few days later at a dinner party, Holmes was discussing this issue to the Martin Hall, the Minister of Transportation, a newly created position. Hall had previously received complaints of a similar nature and decided to act. By placing two lines, spaced 6 inches apart, the incidence of mirror/mirror collisions were greatly reduced and resulted in the double line that we are accustomed to seeing today.

¹Holmes is most notably known for his work leading to the invention of the screw mason jar in 1885, which replaced the clamp-top.

Magnetic Salmon and Sustainable Fishing

At the turn of the 20th century, there were several reports of various fishing and shipping vessels having Atlantic Salmon (Salmo salar) stuck to the side of the hull. During this period the hulls on the vessels were still made almost completely out of iron. The reports at the time theorized that some kind of magnetic current was holding the fish to the hulls. Little attention was paid to the reports and it fell into obscurity and theoccurrences stopped with the rise of alloy hulls.

However, in 2002, Dr. Eilert Moen, whose grandfather had been aboard a vessel who has reported an instance of the salmon phenomenon, began research on these occurrences in the hopes of developing a sustainable fishing practice, one that could be used to replace bottom trawling and large, environmentally unfriendly nets. In 2003, in a paper entitled Electromagnetic Attraction of Salmo spp. to Marine Ferris Objects, he determined that Atlantic Salmon have an enzyme called Therrase, which is used to aid in the digestion on amphipods. He proposed that when a certain current is induced in the water, it flips the enzyme, causing it to become slightly magnetic. This causes the fish to be attracted to the large charged metallic objects, such as hulls. Current research is being completed to try to determine what current is most effective at flipping Therrase through large bodies of water.

Dr. Moen hypothesizes that if this current could be induced on a large enough scale, the fishing industry could be revolutionized. Fishing for Atlantic salmon could be accomplished by sending a current through the water, which would flip the Therrase enzyme in nearby fish. These fish could then be harvested using large magnets, which would be a much more sustainable fishing practice as compared to current methods, which includes bottom trawling. If implemented, this current would cause only the Atlantic salmon to be attracted to the magnets, thus reducing the damaging effects of the fishing industry. "World fisheries are in decline, it is projected that they will collapse by the year 2050. Practices like these can reduce our impact on the world and other living species", said Dr. Moen in a recent interview.