c. 1960's vintage american medical chicago public school science classroom three-dimensional dna molecule model designed and fabricated by the science teaching aids, pell lake, wisc. the kit consists of molded rubber strands, color-coded based (i.e., a,g,t,c) steel rods and pedestal bases. the freestanding molecule assemblage comes with directions and original portable storage case with drop handle. the components are in great overall condition, considering age. the easy-to-assemble dna replica is color-coded for proper base pair alignment. the heavily illustrated guides for teachers and students is free from damage. the dna molecule assembly kit was salvaged from a chicago public school. skeletons, fossils, painted wood molecules and vintage posters are available as well. late in 1951, francis crick started working with james watson at cavendish laboratory at the university of cambridge, england. using "photo 51" (the x-ray diffraction results of rosalind franklin and her graduate student raymond gosling of king's college london, given to them by gosling and franklin's colleague maurice wilkins), watson and crick together developed a model for a helical structure of dna, which they published in 1953. for this and subsequent work they were jointly awarded the nobel prize in physiology or medicine in 1962 with maurice wilkins. measures 17 1/2 x 7 x 21 inches.