glBegin(GL_LINE_STRIP);

z = -50.0f;
for(angle = 0.0f; angle <= (2.0f*3.1415f)*3.0f; angle += 0.1f)
	{
	x = 50.0f*sin(angle);
	y = 50.0f*cos(angle);

	// Specify the point and move the Z value up a little
	glVertex3f(x, y, z);
	z += 0.5f;
	}

// Done drawing points
glEnd();