This is the second paper in a series on large-amplitude delta Scuti stars intended to determine Baade-Wesselink radii and luminosities with precision. The first paper (Wilson et al., 1993PASP..105..809W) discussed our method of analysis and its application to EH Librae; in this we discuss the observations and analysis of DY Herculis. Optical and infrared photometry and cross-correlated radial-velocity data have been obtained and analyzed. Fourier representations for the UBVRIJHK light curves and for the radial-velocity curves were used to derive a value for the minimum radius for each of 60 combinations of flux and color index. From these we adopt a mean value for the minimum radius of R_min_=2.77+/-0.20R_{sun}_. When combined with effective temperatures from Breger et al. (1978PASP...90..754B), we find a mean bolometric luminosity of <L_B_>=21.70L_{sun}_ and a mean absolute magnitude of <M_B_>=1.41. The radial excursion is 0.149R_{sun}_. We use the same procedure to improve our results for EH Librae, deriving R_min_ for each of 42 combinations of flux and color index, and obtain mean values of R_min_=2.62+/-0.19R_{sun}_, <L_B_>=24.56L_{sun}_ and <M_B_>=1.27. Addresses: Milone E.F. milone@acs.ucalgary.ca Wilson W.J.F. wjfwilso@acs.ucalgary.ca Fry D.J.I. fry@acs.ucalgary.ca Rothney Astrophysical Observatory, Department of Physics and Astronomy, University of Calgary, 2500 University Drive, NW, Calgary AB T2N 1N4, Canada Schiller S.J. SchilleS@mg.sdstate.edu Physics Department, South Dakota State University, Box 2219, Brookings, South Dakota 57007-0395