In spite of the fact that in the very early years of the 20th century the horse was the principal mode of transportation for Dominicans, there were already people looking for oil in the Dominican Republic. The areas of Higuerito and Maleno were where people believed that there might be oil. And they still do. Gerald Ellis and Nestor Rodriguez have written a book called “The History of Oil in the Dominican Republic”, and they affirm that between 1901 and 1903, some wells were dug in Higuerito. Between 1904 and 1907, the firm Lancaster and Krieder drilled seven wells in Higuerito at depths of between 129 and 935 feet. The deepest well during the early years was 1,200 feet and it produced 200 barrels a day until the pressure fell and the well was capped. In 1920, 1927 and 1928 more test wells were drilled. The authors mention how Esso was the first oil company to begin operations in the country in 1904, followed by Texaco in 1915 and Shell in 1927. At the present time geologists are interested in the Bay of Ocoa as a possible site for new drilling, since the area was studied by Tenneco in 1969 and by Mobil in 1991.