A capillary bridge viscometer (120), comprises at least two at least generally balanced bridge arm conduits (R1, R2) a bulkhead supporting structure (122,134) supporting removable connection portions for each of a plurality of the arms in a bridge configuration, a bridge supporting structure (124,136) supporting the bridge arm conduits (R1,R2) and supporting two further removable connection portions (132) for each of the bridge arm conduits, wherein each of the further removable connection portions (132) supported by the bridge supporting structure are positioned to mate with a corresponding one of the removable connection portions (130) supported by the bulkhead supporting structure concurrently to hydraulically connect the bridge arm conduits in the bridge configuration; and a balance detector having hydraulic connections for connection between first and second differential detection points in the bridge when the removable connection portions on the bridge are mated to corresponding ones of the removable connection portions supported by the bulkhead supporting structure.