Dutch Blue & White Royal Delft Commemorative Plate 13th Concilium Ophthalmologicum 1929

The small tin glazed earthenware plate decorated in shades of blue with a perched owl between a candle holder with a burning candle and a pair of glasses and the text:
Wat Baet er Kaers of Bril ,
As den Uyl niet Sien en Wil.
What use is candle or glasses, as the owl don’t see and want. 

Dit wordt gezegd als men tevergeefs zijn best doet om iemand, die dom of eigenwijs is, beter in te lichten
On the rim with stylized floral swags the Latin text:
CONCILIUM OPHTHALMOLOGICUM - 1929
Signed on the back in underglaze blue for:
DE PORCELEYNE FLES  -  ROYAL DELFT
DELFT  -  HOLLAND  &  AY = 1929
Two painters worded on this plate:
Painter’s initials: VH  = Gijsbertus van Heijenoort.
Employment dates: 1891 - 1940.
Painter’s initials: VK  = Antonius Johannes van Kampenhout.
Employment dates: 1892 - 1942

Diam.:  14 cm.  (5,5 inches.)      
Weight: 132 grams.