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WonderRoad safety design fact

Cat's eyes, the small reflectors set into the middle of many roads, were invented by Percy Shaw of Halifax, England, and patented in 1934. They send headlight beams back towards the driver, and when a wheel rolls over them a rubber wiper cleans the glass.

Cat's eye road stud

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The story behind the card

Shaw said he had found his way home on dark nights by the shine of tram rails; once they were removed, he needed something else to follow. The name comes from the way a cat's eyes glow in headlights. Each stud holds glass lenses in a rubber dome set in a cast-iron base. A passing wheel pushes the dome down, a fixed rubber wiper cleans the lenses as they sink, and rainwater collecting in the base helps rinse them. Shaw set up his company in Halifax in 1935. During the Second World War blackouts, when street lights were off and headlights were partly covered, their value became obvious, and after the war a Ministry of Transport committee backed their use across Britain's roads. Similar studs are now used around the world.

Türkçe oku
Yol ortasındaki küçük reflektörleri, yani kedi gözlerini, İngiltere'nin Halifax kentinden Percy Shaw icat etti ve 1934'te patentini aldı. Farların ışığını sürücüye geri yansıtırlar; üzerlerinden bir tekerlek geçtiğinde de kauçuk bir silecek camlarını temizler.

Shaw, karanlık gecelerde evinin yolunu tramvay raylarının parıltısına bakarak bulduğunu, raylar sökülünce izleyecek başka bir şeye ihtiyaç duyduğunu anlatmıştı. Adını, kedi gözlerinin far ışığında parlamasından alır. Her birinde, dökme demir bir tabana oturan kauçuk bir kubbenin içinde cam mercekler bulunur. Üzerinden geçen tekerlek kubbeyi aşağı bastırır, mercekler çökerken sabit bir kauçuk silecek onları temizler; tabanda biriken yağmur suyu da yıkanmalarına yardım eder. Shaw şirketini 1935'te Halifax'ta kurdu. İkinci Dünya Savaşı'ndaki karartmalarda sokak lambaları söndürülüp farlar kısmen kapatılınca kedi gözlerinin değeri açıkça görüldü. Savaştan sonra Ulaştırma Bakanlığı'nın bir komitesi, İngiltere yollarında yaygınlaşmalarını destekledi. Benzerleri bugün dünyanın her yerinde kullanılıyor.

Sources and further reading

Background reading: Cat's eye (road)
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