Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
List of ambassadors of the United States to Australia
Table title:
United States Ambassadors to Australia
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Ordinal </th><th colspan=1 rowspan=1 > Officeholder </th><th colspan=1 rowspan=1 > Image </th><th colspan=1 rowspan=1 > Term began </th><th colspan=1 rowspan=1 > Term ended </th><th colspan=1 rowspan=1 > Time in office </th><th colspan=1 rowspan=1 > Notes </th></tr>
<tr> <th colspan=7 rowspan=1 > US Ministers to Australia </th></tr>
<tr> <td colspan=1 rowspan=1 > 1 </td><td colspan=1 rowspan=1 > Clarence E. Gauss </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 1940 </td><td colspan=1 rowspan=1 > 1941 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 2 </td><td colspan=1 rowspan=1 > Nelson T. Johnson </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 1941 </td><td colspan=1 rowspan=1 > 1945 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <th class="highlighted"  colspan=7 rowspan=1 > US Ambassadors to Australia </th></tr>
<tr> <td colspan=1 rowspan=1 > 3 </td><td colspan=1 rowspan=1 > Robert Butler </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1946 </td><td colspan=1 rowspan=1 > 1948 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 4 </td><td class="highlighted"  colspan=1 rowspan=1 > Myron M. Cowen </td><td colspan=1 rowspan=1 >  </td><td class="highlighted"  colspan=1 rowspan=1 > 1948 </td><td class="highlighted"  colspan=1 rowspan=1 > 1949 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 5 </td><td colspan=1 rowspan=1 > Pete Jarman </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 8 June 1949 </td><td colspan=1 rowspan=1 > 31 July 1953 </td><td colspan=1 rowspan=1 > 4 years, 53 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 6 </td><td colspan=1 rowspan=1 > Amos J. Peaslee </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1953 </td><td colspan=1 rowspan=1 > 1956 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 7 </td><td colspan=1 rowspan=1 > Douglas M. Maffat </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1956 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 8 </td><td colspan=1 rowspan=1 > William J. Sebald </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 14 March 1957 </td><td colspan=1 rowspan=1 > 31 October 1961 </td><td colspan=1 rowspan=1 > 4 years, 231 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 9 </td><td colspan=1 rowspan=1 > William C. Battle </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 13 July 1962 </td><td colspan=1 rowspan=1 > 31 August 1964 </td><td colspan=1 rowspan=1 > 2 years, 49 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 10 </td><td colspan=1 rowspan=1 > Ed Clark </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1965 </td><td colspan=1 rowspan=1 > 1967 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 11 </td><td colspan=1 rowspan=1 > William H. Crook </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1968 </td><td colspan=1 rowspan=1 > 1969 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 12 </td><td colspan=1 rowspan=1 > Marshall Green </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1969 </td><td colspan=1 rowspan=1 > 1973 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 13 </td><td colspan=1 rowspan=1 > Walter L. Rice </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1973 </td><td colspan=1 rowspan=1 > 1975 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 14 </td><td colspan=1 rowspan=1 > James W. Hargrove </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1976 </td><td colspan=1 rowspan=1 > 1977 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 15 </td><td colspan=1 rowspan=1 > Philip H. Alston </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1977 </td><td colspan=1 rowspan=1 > 1981 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 16 </td><td colspan=1 rowspan=1 > Robert D. Nesen </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 20 November 1981 </td><td colspan=1 rowspan=1 > 2 May 1985 </td><td colspan=1 rowspan=1 > 3 years, 163 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 17 </td><td colspan=1 rowspan=1 > Laurence W. Lane </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 6 December 1985 </td><td colspan=1 rowspan=1 > 29 April 1989 </td><td colspan=1 rowspan=1 > 3 years, 144 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 18 </td><td colspan=1 rowspan=1 > Melvin F. Sembler </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 10 October 1989 </td><td colspan=1 rowspan=1 > 28 February 1993 </td><td colspan=1 rowspan=1 > 3 years, 141 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 19 </td><td colspan=1 rowspan=1 > Edward J. Perkins </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 24 November 1993 </td><td colspan=1 rowspan=1 > 19 July 1996 </td><td colspan=1 rowspan=1 > 2 years, 238 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 20 </td><td colspan=1 rowspan=1 > Genta H. Holmes </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 > 1997 </td><td colspan=1 rowspan=1 > 2000 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 21 </td><td colspan=1 rowspan=1 > Edward (Skip) Gnehm </td><td colspan=1 rowspan=1 > EdwardGnehm.JPG </td><td colspan=1 rowspan=1 > 2000 </td><td colspan=1 rowspan=1 > 2001 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 22 </td><td colspan=1 rowspan=1 > Thomas Schieffer </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 23 August 2001 </td><td colspan=1 rowspan=1 > 18 February 2005 </td><td colspan=1 rowspan=1 > 3 years, 179 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 23 </td><td colspan=1 rowspan=1 > Robert McCallum, Jr. </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 2006 </td><td colspan=1 rowspan=1 > 2009 </td><td colspan=1 rowspan=1 >  </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 24 </td><td colspan=1 rowspan=1 > Jeff Bleich </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 26 November 2009 </td><td colspan=1 rowspan=1 > 12 September 2013 </td><td colspan=1 rowspan=1 > 3 years, 290 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 25 </td><td colspan=1 rowspan=1 > John Berry </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 25 September 2013 </td><td colspan=1 rowspan=1 > October 2016 </td><td colspan=1 rowspan=1 > 3 years, 6 days </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=4 rowspan=1 > vacant </td><td colspan=1 rowspan=1 > October 2016 </td><td colspan=1 rowspan=1 > 12 March 2019 </td><td colspan=1 rowspan=1 >  </td></tr>
<tr> <td colspan=1 rowspan=1 > 26 </td><td colspan=1 rowspan=1 > Arthur B. Culvahouse Jr. </td><td colspan=1 rowspan=1 > - </td><td colspan=1 rowspan=1 > 13 March 2019 </td><td colspan=1 rowspan=1 > present </td><td colspan=1 rowspan=1 > 25 days </td><td colspan=1 rowspan=1 >  </td></tr>
</table>
Question:
What were Myron Cowen's accomplishments during the years 1948 and 1949?
Answer:
Myron M. Cowen was appointed as the US Ambassador to Australia from 1948 to 1949.