The Rapid Symmetrical was a general purpose lens of the rapid rectilinear type produced in sizes from 3 - 34". It replaced the Actinic Doublet and was in turn replaced by the Symmetrical Anastigmat around 1900. The rear half could be used separately having a focal length about twice that of the complete lens.

J.H. Dallmeyer's original patent for the rapid rectilinear (BP 2502/1866) describes a lens of "two positive achromats of which the higher refracting denser material or flint glass occupies the external position of each combination". The inner pair of glasses were of crown glass. The diameter of the back combination was half that of the front. In production both lens groups were of the same diameter and an extra light flint glass was used for the inner pair of glasses.

Crouch produced a range of conventional rapid rectilinear lenses and a faster model for hand cameras in lengths from 4 ½ - 6".

Made in sizes from 6 - 18" and later 24".

The Euryscope was produced in several series.

• Series IV at f6.3
• Series VI at f7.7
• Series III at f4.5
• Series IVa at f7
• Series VIIa wide-angle at f18

The Detective lens was a rapid rectilinear type in a short mount especially suited to hand cameras. It was produced in lengths of 4 ½ to 6".

The Detective Paragon was made with the new Jena glass. Produced specifically for hand cameras in lengths of 3 - 5 ½".