Badge of the mathematical scholars of Christ's Hospital, uniface in thin plate. Obverse: Three figures, two being female, stand on the sea-shore with a Bluecoat boy in the foreground. One representing Arithmetic (left) holds a tablet, her left hand resting upon the boy's head. Mathematics holds a triangle and compasses (centre) and the male figure of Astronomy holding an armillary sphere (right) with a cross staff visible above his right shoulder. Above on clouds the infant Fame is shown blowing a trumpet and one cherub holds a caduceus, signifying genius. Zephyrs blow a favourable wind upon ships below in distance (left). Legend: 'AVSPICIO CAROL SECVNDI . REGIS . 1673.' (Under the auspice of King Charles II.)

These silver badges were struck for sewing to the coats of the 40 mathematical scholars of the nautical school - known as the Royal Mathematical Foundation - established within Christ's Hospital School (the Bluecoat school) in 1672 by Charles II.

This is a mint-condition unperforated example, but they were usually pierced round the rim for sewing: PLT0746 is a pierced example. The design is a simplified variation of the reverse of the foundation medal of the mathematical school, also by Roettier (see MEC0878). It is assumed they were struck in batches, the early ones being silver but none being hall-marked. They are therefore not precisely dateable except to say that at some point in the mid-18th century, when it was found that boys were selling them for their silver value, they were replaced with the same design in silver plate. In 1686 Henry Stone provided funds for a further 12 mathematical scholars, who had a different silver badge, of which the die was paid for by Sir Isaac Newton. This was also later changed to plate for the same reason.

Mathematician Robert Hooke, who was a governor of Christ’s Hospital, appears to have played a part in the badge’s design. In his diary, Hooke wrote on 21 January 1673/4 that he had created a design for a badge that had ‘two circles encompassing a prospect, with a crown over, and a label under the circles was written, Ambit et fovet [it strives and cherishes], in the label, a Carolo II dats fuit [it was given by Charles II], in the prospect was a blew [blue] coat boy attended by Geometry, Arithmetic and Astronomy, with hac via itur a[d] astra [this way leads to the stars]. At a distance the Herculean pillar, passed through with a ship and over and far off, terra icognita.’

This description has similarities with the final design of the badge, but there are some marked differences, suggesting that the Hospital’s Governors requested modifications to Hooke’s proposal. The final design excludes the crown, has different inscriptions and features additions such as cherubs and zephyrs blowing two ships along and a mariner’s compass and lead.

The badge was engraved at the Royal Mint by the Roettier brothers. Three brothers of this name worked at the Royal Mint at this time, Joseph, Philip and John. It has historically been suggested that John Roettier engraved the badge, but it was in fact his brother Joseph who signed receipts for payments from Christ’s Hospital and Philip’s name later appears in the school’s account books. Joseph left the Royal Mint in 1679, Philip in 1685 and John in 1689.