Daniel Chapman Stillson the J. J. Walworth Company in the Cambridgeport section of Cambridge, Massachusetts. While at the J. J. Walworth Company, he developed his pipe wrench. On September 13, 1870, he was issued his patent. Stillson was paid about $80,000 in royalties during his lifetime. He died on August 23, 1899, and is buried at Mount Auburn Cemetery in Cambridge and Watertown, Massachusetts. Daniel Chapman Stillson Daniel Chapman Stillson (March 25, 1826 - August 23, 1899) was an American inventor. He invented the modern adjustable pipe wrench. He was born March 25, 1826 in Durham, New Hampshire. He was the son of
Transposons as a genetic tool The recent discovery of the 'mariner transposon' (from the reconstruction of the original sequence from many 'dead' versions in the human genome) has allowed many new experiments, mariner has well conserved homologues across a wide range of species and is a very versatile tool. Transposons as a genetic tool Transposons are semi-parasitic DNA sequences which can replicate and spread through the host's genome. They can be harnessed as a genetic tool for analysis of gene and protein function. The use of transposons is well-developed in "Drosophila" (in which P elements are most commonly used) and in Thale cress ("Arabidopsis thaliana")