Seven Of stars, namely, HD 17603 07.5 If, HD 34656 O7 11(f), HD 188001 9 Sge 07.5 Iaf, HD 190864 06.5 111(f), HD l92639 O71b(f), HD l935l4 O7 Ib(f), and HD 210839 λCep 06 I(n)fp, have been observed at 30 Åmm-1 in the blue-violet, yellow-green, and red regions. The above are Walborn spectral types. All the spectrograms were measured for radial velocity, and the results are presented.Each star is discussed separately, and the results are summarized. The spectrum of each star has been classified using the ratio W' = Wλ( He I λ4471)/Wλ (He IIλ4541) to determine the spectral type; the Stark effect broadening of the lines of the Pickering series of He II has been used to determine the luminosity class. The question of appropriate luminosity and spectral type criteria is discussed in 3.10 and 3.11. The generally accepted luminosity criteria for stars of types O8 and earlier are found to be ambiguous, while the traditional criterion for spectral type among the O stars is found to be sensitive to factors in addition to the effective temperature of the star. New spectral types are recommended for the program stars. They are: HD 17603 O8 Ifv, HD 34656 07.5 III((f)), HD 188001 9 Sge O8 If, HD 190864 O7 III((f)), HD 192639 O8 Ifv, HD 193514 07.5 I(f), and HD 210839 λ Cep 06.5 IIIfp. The letter v is introduced in two cases to indicate that the Of subtype has been observed to change from f to (f). It is suggested that the peculiar character of the spectrum of λ Cep indicates the presence of a disk; the Stark broadening of the He II lines of this star clearly indicate that λ Cep is a giant rather than a supergiant. The profiles of Hα and He II λ4686 indicate that the physical state/degree of ionization of the winds of HD 17603, HD 188001 9 Sge, HD 192639, and HD 210839 λ Cep change. The timescale of the changes has been observed to be hours for λ Cep, a few days for HD 192639, and months or years for HD 188001 9 Sge and HD 17603. These changes in the physical state of the wind occur with no detected change in the luminosity of the star or of its spectral type. The star HD 188001 9 Sge is confirmed to be a SB1 with a period of 78.74 days and small range. The stars HD 190864 and HD 192639 would benefit from intense observation over 10-14 days to determine whether or not they are SB 1 stars of small range. In some of the stars (see the notes on each star) the sharp emission lines are displaced relative to lines formed in the photosphere. The weak sharp emission lines appear to close to the photosphere and to rotate with the photosphere. Four new emission lines are seen near 6720 Å. Some support is adduced for the model for O stars described by Underhill (1984).