I'm now using XYSeries with ScatterPlot and it's working much better.  Thanks Max.

Sorry, but LineChart types cannot use a numeric X axis. If you're using a line chart the x axis is a string type and every label is interpreted as a string. That's basically like taking a log of "apples". You should use a scatter chart and replace NumericSeries with XYSeries, where you have to specify the x and the y values. As for having a line, simply set chart.ScatterChart.ConnectWithLines = true

I see.
I was able to reproduce the graph that you have attached using the same data and using a ScatterChart.
However, on my above chart, I was using a line chart and a Numeric Series.  I still get the chart with two lines and non-equally spaces X-Axis.
NumericSeries pSeries = new NumericSeries();
for (int i = 1; i < 75, ++i)
{
  String sLabel = Convert.ToString( i*10 );
  pSeries.Points.Add( new NumericDataPoint( i*10, sLabel, false );
}

m_Chart.Axis.X.MajorGridLines.Visible = true;
m_Chart.Axis.X.LogBase = 10;
m_Chart.Axis.X.NumericAxisType = NumericAxisType.Logarithmic;
m_Chart.Axis.X.TickmarkStyle = AxisTickStyle.DataInterval;
m_Chart.Axis.X.TickmarkInterval = 1;
m_Chart.ChartType = ChartType.LineChart;
m_Chart.Series.Clear();
m_Chart.Series.Add( pSeries );

Is there a way to get the same result with a LineChart?  Also, if I use scatter plot, can I get it to use the NumericDataSeries?

Let me know if you need more code.

DataTable dt = new DataTable();
dt.Columns.Add("col1", typeof(int));
dt.Columns.Add("col2", typeof(int));
for (int i = 10; i < 2000; i++)
{
  dt.Rows.Add(new object[ { i, i*10 });
}

ultraChart1.ChartType = ChartType.ScatterChart;
ultraChart1.Data.DataSource = dt;
ultraChart1.ScatterChart.ColumnX = 0;
ultraChart1.ScatterChart.ColumnY = 1;
ultraChart1.Axis.X.NumericAxisType = NumericAxisType.Logarithmic;
ultraChart1.Axis.X.TickmarkStyle = AxisTickStyle.DataInterval;
ultraChart1.Axis.X.TickmarkInterval = 1;