A collection of 3 single button chronographs

TH. Picard & Fils, La Chaux de Fonds, Case No. 218102, 39 mm, circa 1915

A rare single button chronograph
Case: 18k gold, push back. Dial: enamel, Arabic numerals, auxiliary seconds, 30 min. counter, red tachy scale, signed, blued spade hands. Movm.: 2/3 plate movement, nickel-plated, ground, finely ground chronograph steel parts, ratchet wheel, monometallic screw balance.