Synopsis of the Illustrated Guide

[bradl]

An excerpt and several illustrations from the CTCA's excellent Illustrated Guide to the Cairn Terrier ... via Showsight magazine: 

The Cairn Terrier: A synopsis of the Illustrated Guide of the Cairn Terrier

Quote

GENERAL APPEARANCE

The Cairn is a study in contrasts—he is a “big” dog in a small package; nothing about the dog is delicate. He has a medium length of leg—neither short nor long. There should be some daylight under the Cairn. He is a working terrier and needs sufficient length of leg to climb or jump over rough terrain. A great word picture was created when one of the founders of the breed, Mrs. Alastair Campbell, was quoted as saying “They should be light-footed and almost dance along... like polo ponies, sturdy but light in their action and body.” Thus, a Cairn should be lithe, flexible and athletic.

Much more in the linked article and even more in the guide itself. Get it from the CTCA. 

[Sam I Am]

I find the standard size interesting as I have seen Cairns in the show ring that are very much bigger in size. Sams dad for one that has won many championships inCanada and the US..and he is as big as Sam who weighs in at 19 pounds. Has the standard size changed or is it just the whole package that counts more than the size ?

[bradl]

The standard describes an ideal.

It is taken as a whole and up to the judge to evaluate how deviations from the ideal for each specific dog affect that dog's embodiment of the ideal when compared to other dogs in the ring that day (each with their own deviations).

The 1921 and 1925/1926 versions of the standard had a points scale to weigh (no pun intended) some aspects more or less than others. For example 'size' might be assessed by a judge in the category of 'body' and was worth 20 points on the scale. However since 1938 the standard has not had a scale of points.

Somewhat related, the standard lists Faults but not Disqualifications. Standards that include Disqualifications mean a dog possessing them is dismissed (from the ring) without further consideration. 

The portion of the standard dealing with size differs slightly between the US standard and the FCI version used everywhere else.

FCI

Quote

SIZE: Approximately 28-31 cm (11-12 ins) at withers, but in proportion to weight-ideally 6-7,5 kg (14-16 lbs).

AKC

Quote

Ideal Size: Involves the weight, the height at the withers and the length of body. Weight for bitches, thirteen pounds; for dogs, fourteen pounds. Height at the withers, bitches nine and a half inches; dogs, ten inches. Length of body from fourteen and a quarter to fifteen inches from the front of the chest to back of hindquarters. The dog must be of balanced proportions and appear neither leggy nor too low to ground; and neither too short nor too long in body. Weight and measurements are for mature dogs at two years of age. Older dogs may weigh slightly in excess and growing dogs may be under these weights and measurements.