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This paper reports on the spectroscopic investigation of 238 Cepheids in thenorthern sky. Of these stars, about 150 are new to the study of the galacticabundance gradient. These new Cepheids bring the total number of Cepheidsinvolved in abundance distribution studies to over 400. In this work we alsoconsider systematics between various studies and also those which result fromthe choice of models. We find systematic variations exist at the 0.06 dex levelboth between studies and model atmospheres. In order to control the systematiceffects our final gradients depend only on abundances derived herein. A simplelinear fit to the Cepheid data from 398 stars yields a gradient d[Fe/H]/dRG =-0.062 \pm 0.002 dex/kpc which is in good agreement with previously determinedvalues. We have also reexamined the region of the "metallicity island" of Lucket al. (2006). With the doubling of the sample in that region and ourinternally consistent abundances, we find there is scant evidence for adistinct island. We also find in our sample the first reported Cepheid (V1033Cyg) with a pronounced Li feature. The Li abundance is consistent with the starbeing on its red-ward pass towards the first giant branch.

The Distribution of the Elements in the Galactic Disk III. A Reconsideration of Cepheids from l = 30 to 250 Degrees