The Seamstress. Oil On Canvas, 19th Century. Signed?

French School, circa 1850 or 1860. Oil on canvas in good condition. However, minor restoration is needed (very little) on the stool where the basket containing fabrics rests. There are a few fine craquelure and two scratches. The composition is superb, depicting an embroiderer in a richly detailed interior: a hanging violin, a calendar, books, maps, drawing boards, an inkwell, and a lamp. A window opens onto the rooftops and chimneys of Paris, all contributing to a calm and pleasant atmosphere. A true success. The canvas has been enlarged by two centimeters at the top. Dimensions: 47.6 cm x 37.5 cm. I present it in an antique frame with its original gilding, though some minor losses are present, measuring 55.5 cm x 47.3 cm. The painting bears a beautiful signature in the lower left corner, which I have not been able to identify: H. Gruyer.