EPSG:4300

GEOGCS["TM75",DATUM["D_TM75",SPHEROID["Airy_Modified_1849",6377340.189,299.3249646]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]]

+proj=longlat +ellps=mod_airy +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +no_defs 

proj4.defs("EPSG:4300","+proj=longlat +ellps=mod_airy +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +no_defs");

<?xml version="1.0" encoding="UTF-8"?>
 <gml:GeodeticCRS xmlns:epsg="urn:x-ogp:spec:schema-xsd:EPSG:1.0:dataset" xmlns:gml="http://www.opengis.net/gml/3.2" xmlns:xlink="http://www.w3.org/1999/xlink" gml:id="epsg-crs-4300">
   <gml:metaDataProperty>
      <epsg:CommonMetaData>
         <epsg:type>geographic 2D</epsg:type>
         <epsg:alias alias="1975 Mapping Adjustment" code="1308" codeSpace="urn:ogc:def:naming-system:EPSG::7301" />
         <epsg:informationSource>"The Irish Grid - A Description of the Co-ordinate Reference System" published by Ordnance Survey of Ireland, Dublin and Ordnance Survey of Northern Ireland, Belfast.</epsg:informationSource>
         <epsg:revisionDate>2004-01-06</epsg:revisionDate>
         <epsg:changes>
            <epsg:changeID xlink:href="urn:ogc:def:change-request:EPSG::2002.621" />
            <epsg:changeID xlink:href="urn:ogc:def:change-request:EPSG::2003.370" />
         </epsg:changes>
         <epsg:show>true</epsg:show>
         <epsg:isDeprecated>false</epsg:isDeprecated>
      </epsg:CommonMetaData>
   </gml:metaDataProperty>
   <gml:identifier codeSpace="OGP">urn:ogc:def:crs:EPSG::4300</gml:identifier>
   <gml:name>TM75</gml:name>
   <gml:remarks>Uses Geodetic Datum of 1965 which should not be confused with the 1965 adjustment (TM65, datum code 6299 and CRS code 4299). Replaces OSNI52 (CRS code 4188) and TM65 (CRS code 4299). Replaced by IRENET95 (CRS code 4173).</gml:remarks>
   <gml:domainOfValidity xlink:href="urn:ogc:def:area:EPSG::1305" />
   <gml:scope>Basis for topographic mapping.</gml:scope>
   <gml:ellipsoidalCS xlink:href="urn:ogc:def:cs:EPSG::6422" />
   <gml:geodeticDatum xlink:href="urn:ogc:def:datum:EPSG::6300" />
</gml:GeodeticCRS>

<?xml version="1.0" encoding="UTF-8"?>
 <gml:GeographicCRS gml:id="ogrcrs252880" xmlns:gml="http://www.opengis.net/gml/3.2">
  <gml:srsName>TM75</gml:srsName>
  <gml:srsID>
    <gml:name gml:codeSpace="urn:ogc:def:crs:EPSG::">4300</gml:name>
  </gml:srsID>
  <gml:usesEllipsoidalCS>
    <gml:EllipsoidalCS gml:id="ogrcrs252881">
      <gml:csName>ellipsoidal</gml:csName>
      <gml:csID>
        <gml:name gml:codeSpace="urn:ogc:def:cs:EPSG::">6402</gml:name>
      </gml:csID>
      <gml:usesAxis>
        <gml:CoordinateSystemAxis gml:id="ogrcrs252882" gml:uom="urn:ogc:def:uom:EPSG::9102">
          <gml:name>Geodetic latitude</gml:name>
          <gml:axisID>
            <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9901</gml:name>
          </gml:axisID>
          <gml:axisAbbrev>Lat</gml:axisAbbrev>
          <gml:axisDirection>north</gml:axisDirection>
        </gml:CoordinateSystemAxis>
      </gml:usesAxis>
      <gml:usesAxis>
        <gml:CoordinateSystemAxis gml:id="ogrcrs252883" gml:uom="urn:ogc:def:uom:EPSG::9102">
          <gml:name>Geodetic longitude</gml:name>
          <gml:axisID>
            <gml:name gml:codeSpace="urn:ogc:def:axis:EPSG::">9902</gml:name>
          </gml:axisID>
          <gml:axisAbbrev>Lon</gml:axisAbbrev>
          <gml:axisDirection>east</gml:axisDirection>
        </gml:CoordinateSystemAxis>
      </gml:usesAxis>
    </gml:EllipsoidalCS>
  </gml:usesEllipsoidalCS>
  <gml:usesGeodeticDatum>
    <gml:GeodeticDatum gml:id="ogrcrs252884">
      <gml:datumName>Geodetic_Datum_of_1965</gml:datumName>
      <gml:datumID>
        <gml:name gml:codeSpace="urn:ogc:def:datum:EPSG::">6300</gml:name>
      </gml:datumID>
      <gml:usesPrimeMeridian>
        <gml:PrimeMeridian gml:id="ogrcrs252885">
          <gml:meridianName>Greenwich</gml:meridianName>
          <gml:meridianID>
            <gml:name gml:codeSpace="urn:ogc:def:meridian:EPSG::">8901</gml:name>
          </gml:meridianID>
          <gml:greenwichLongitude>
            <gml:angle gml:uom="urn:ogc:def:uom:EPSG::9102">0</gml:angle>
          </gml:greenwichLongitude>
        </gml:PrimeMeridian>
      </gml:usesPrimeMeridian>
      <gml:usesEllipsoid>
        <gml:Ellipsoid gml:id="ogrcrs252886">
          <gml:ellipsoidName>Airy Modified 1849</gml:ellipsoidName>
          <gml:ellipsoidID>
            <gml:name gml:codeSpace="urn:ogc:def:ellipsoid:EPSG::">7002</gml:name>
          </gml:ellipsoidID>
          <gml:semiMajorAxis gml:uom="urn:ogc:def:uom:EPSG::9001">6377340.189</gml:semiMajorAxis>
          <gml:secondDefiningParameter>
            <gml:inverseFlattening gml:uom="urn:ogc:def:uom:EPSG::9201">299.3249646</gml:inverseFlattening>
          </gml:secondDefiningParameter>
        </gml:Ellipsoid>
      </gml:usesEllipsoid>
    </gml:GeodeticDatum>
  </gml:usesGeodeticDatum>
</gml:GeographicCRS>

4300=GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646,AUTHORITY["EPSG","7002"]],TOWGS84[482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15],AUTHORITY["EPSG","6300"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]]

PROJECTION
	"proj=longlat"
	"ellps=mod_airy"
	"towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15"
	"no_defs"
END

<?xml version="1.0" encoding="utf-8"?>
<Map srs="+proj=longlat +ellps=mod_airy +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +no_defs">
	<Layer srs="+proj=longlat +ellps=mod_airy +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +no_defs">
	</Layer>
</Map>

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 4300, 'EPSG', 4300, '+proj=longlat +ellps=mod_airy +towgs84=482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15 +no_defs ', 'GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646,AUTHORITY["EPSG","7002"]],TOWGS84[482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15],AUTHORITY["EPSG","6300"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]]');

GEOGCS["TM75",DATUM["Geodetic_Datum_of_1965",SPHEROID["Airy Modified 1849",6377340.189,299.3249646,AUTHORITY["EPSG","7002"]],TOWGS84[482.5,-130.6,564.6,-1.042,-0.214,-0.631,8.15],AUTHORITY["EPSG","6300"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degree",0.0174532925199433,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","4300"]]