Concrete curbs will be seven (7) inches thick by sixteen (16) inches deep, laid on a cinder bed six (6) inches thick and twelve (12) inches wide. The surface finish shall extend ten (10) inches down the face from the top. In other respects the specifications for "Concrete Combined Curb and Gutter," Item 41, will apply to "Concrete Curb" both in respect to material, workmanship and manner of payment.