Abstract: A viscometer for sensing or characterizing the stress required to shear a fluid at a given rate includes a pair of members coaxially mounted for relative rotation. Between the members is an annular gap defining a flow path for the fluid. The flow path is configured such that during differential rotation of the members, fluid is caused to flow through the annular gap that is a function of the differential rotation and the viscosity of the fluid. A sensor measures the torque or torque equivalent required to achieve such differential rotation between the members.

Abstract: A viscometer for sensing or characterizing the stress required to shear a fluid at a given rate includes a pair of members coaxially mounted for relative rotation. Between the members is an annular gap defining a flow path for the fluid. The flow path is configured such that during differential rotation of the members, fluid is caused to flow through the annular gap that is a function of the differential rotation and the viscosity of the fluid. A sensor measures the torque or torque equivalent required to achieve such differential rotation between the members.

Abstract: A roof tile clip for securing a roof tile to a roof structure has an elongated body portion secured at a lower end such as through a base portion extending from the body portion to the roof structure and a lip portion at an opposite upper end thereof extending over and engaging a side edge of the roof tile. The lip portion is inclined relative to the body portion by an amount approximately equal to the amount of inclination of the roof tile relative to the roof structure to provide a close, relatively conforming fit of the lip portion with the side edge of the roof tile. The clip is made from a single piece of aluminum. The lip portion is further configured to provide a conforming fit over a ridge at the roof tile's side edge, and includes a neck portion an an acute angle to the body portion so as to fit flat against an angled flat surface at the side of the roof tiles, an intermediate portion extending from the neck-portion and a terminal portion extending from the intermediate portion.