The four-cylinder compound locomotive designed by Gaston du Bousquet for the French Chemin de Fer du Nord, of which two (3.1101 and 3.1102) were built at the company's workshops in 1911, was the first tender locomotive in the world with this wheel arrangement. Named the "Baltic" since it was intended for service on the Paris-Saint Petersburg express, its most remarkable feature was the "en echelon" arrangement of the two low-pressure inside cylinders in order to accommodate the very large bore. One of them was built with a water-tube firebox. Although they were not multiplied, they were the forerunners of the highly successful Nord Pacifics and Super-Pacifics. One survives in the "Musée français du chemin de fer" (French national railway museum) at Mulhouse in eastern France, cut up in sectioned form to display its interior during the World Exhibition in Paris in 1937. Its tender was not preserved.