The watch has a rare dial. Among 38 known examples of ref. 1436 in yellow gold with silver dials, thirteen have applied gold Breguet numerals, nine have applied Arabic ?12, and ?6, with applied short ?bâton? indexes, seven have applied long bâton indexes with double index for ?12,, four have applied Roman ?XII? and ?VI? with applied long ?bâton? indexes, three have applied Arabic ?12, and ?6, with long applied ?bâton? indexes. Only two this one and o. 862714 are like the present watch, making it particularly rare. Patek Philippe split-seconds wrist chronographs date back to 1923 o. 124824, originally sold on October 13, 1923, see the Antiquorum sale of ovember 1999, lot 448. These extremely rare watches are highly important collector's items. Between 1938 and 1971 the majority of them were cased with reference 1436, which was preceded by the legendary ref.130. The present watch comes from a small series of four split-seconds wristwatches 862420-862423 made at the beginning of World War II, when resources and money were scarce. The fact that it was superbly enough adjusted and finished to receive the Seal of Geneva Quality Mark suggests that it was made for a particularly demanding client. The Split-Seconds Chronograph Was designed to time two events which begin simultaneously but conclude at different times, as well as a single event for which an intermediate timing is necessary, such as horse or car racing for example. Patek Philippe was one of the first to introduce modern split-seconds chronographs-as early as 1862 o. 17557, see Antiquorum, October 18, 1992, lot 590. The split-seconds mechanism employs two central chronograph hands. Both hands are started at the same time. One hand, the split-seconds one, can be stopped while the other, the chronograph one, continues to move. The split-seconds hand can be reunited with the chronograph hand in order to time another event. This complication is especially useful during sporting events such as a horse race, a car race or a ski race. Seal of Geneva Quality Mark The best Geneva movements, such as this one, were punched with the Seal of Geneva Quality Mark. This is a trademark of the Office of Geneva Control of Watches established on ovember 6, 1886. Paragraph 3 of the statutes states that the watches awarded the Seal of Geneva Quality Mark must "after examination prove to have a perfect mechanism to ensure regular and durable functioning".