Abstract: An elliptical curve drawing device draws an ellipse having desired minor and major axes along given central axes. The device includes a y-axis movable member movably mounted on a base plate for movement along a y-axis which extends perpendicularly to a straight side of the base plate, and an x-axis movable member movably mounted on the base plate for movement along an x-axis which extends parallel to the straight side. The x- and y-axes are brought into alignment respectively with the major and minor axes of an ellipse to be drawn. The elliptical curve follows the path of movement of a point which is spaced from the circumference of a circle which is concentric with the ellipse and whose radius is A, equal to half of the minor axis of the ellipse, by a distance, parallel to the x-axis, which is equal to B cos.theta. where B is the half of the difference between the major axis 2(A+B) and the minor axis 2A of the ellipse and .theta. is the angle formed between the length B and the x-axis.

Abstract: A template includes a reference panel for bringing the center of a figure to be drawn into exact alignment with the center of a previously drawn figure. The reference panel, when used in combination with a figure panel having figure holes, allows concentric figures to be drawn accurately.

Abstract: A method of the quantitative measurement of antigens and antibodies by reacting an antigen or antibody or a mixture thereof with the corresponding antibody and/or antigen which has been supported on insoluble carrier particles, irradiating the resulting reaction mixture with light of a specific wavelength to measure the intensity of light scattered by the reaction mixture.