function validateTimelineForm()
{
	if ((isEmpty(document.timelineSearch.tlst.value))
		&& (isEmpty(document.timelineSearch.tlfy.value))
		&& (isEmpty(document.timelineSearch.tlty.value)))
	{
		alert("Please enter a search term(s).");
		document.timelineSearch.tlst.focus();
		return false;
	}
	else if (!isValidYear(document.timelineSearch.tlfy))
	{
		alert("Please enter a valid year.");
		document.timelineSearch.tlfy.focus();
		return false;
	}
	else if (!isValidYear(document.timelineSearch.tlty))
	{
		alert("Please enter a valid year.");
		document.timelineSearch.tlty.focus();
		return false;
	}
	else
	{
	    document.timelineSearch.action="/servlet/SciRC";
		document.timelineSearch.submit();
	}
}

function clearTimelineForm()
{
	document.timelineSearch.tlst.value='';
	document.timelineSearch.tlfy.value='';
	document.timelineSearch.tlty.value='';
    document.timelineSearch.tlft.options[0].selected=true;
    document.timelineSearch.tltt.options[0].selected=true;
    document.timelineSearch.n.options[0].selected=true;
	document.timelineSearch.tlst.focus();
}

function isValidYear(param)
{
 	var validYearExp = /^[0-9]*$/;
    return (validYearExp.test(param.value));
}


/*------------------------------------------------
info_off = new Image (110,18);
info_off.src = "/images/scirc/bgbig.gif"

imhotep = new Image (110,18);
imhotep.src = "/images/scirc/bc_off.jpg"
imhotepinfo = new Image
imhotepinfo.src = "/images/scirc/bcinfo.gif"
imhotepon = new Image
imhotepon.src = "/images/scirc/bc_on.jpg"
imhoteponr = new Image
imhoteponr.src = "/images/scirc/bc_onr.jpg"

augustus = new Image
augustus.src = "/images/scirc/1-500_off.jpg"
augustuson = new Image
augustuson.src = "/images/scirc/1-500_on.jpg"
augustusinfo = new Image
augustusinfo.src = "/images/scirc/1-500info.gif"

hagia = new Image
hagia.src = "/images/scirc/501-1000_off.jpg"
hagiaon = new Image
hagiaon.src = "/images/scirc/501-1000_on.jpg"
hagiaonl = new Image
hagiaonl.src = "/images/scirc/501-1000_onl.jpg"
hagiaonr = new Image
hagiaonr.src = "/images/scirc/501-1000_onr.jpg"
hagiainfo = new Image
hagiainfo.src = "/images/scirc/501-1000info.gif"

columbus = new Image
columbus.src = "/images/scirc/1001-1500_off.jpg"
columbuson = new Image
columbuson.src = "/images/scirc/1001-1500_on.jpg"
columbusonl = new Image
columbusonl.src = "/images/scirc/1001-1500_onl.jpg"
columbusinfo = new Image
columbusinfo.src = "/images/scirc/1001-1500info.gif"

shakespeare = new Image
shakespeare.src = "/images/scirc/1501-1600_off.jpg"
shakespeareon = new Image
shakespeareon.src = "/images/scirc/1501-1600_on.jpg"
shakespeareonr = new Image
shakespeareonr.src = "/images/scirc/1501-1600_onr.jpg"
shakespeareinfo = new Image
shakespeareinfo.src = "/images/scirc/1501-1600info.gif"

thanksgiving = new Image
thanksgiving.src = "/images/scirc/1601-1700_off.jpg"
thanksgivingon = new Image
thanksgivingon.src = "/images/scirc/1601-1700_on.jpg"
thanksgivingonr = new Image
thanksgivingonr.src = "/images/scirc/1601-1700_onr.jpg"
thanksgivinginfo = new Image
thanksgivinginfo.src = "/images/scirc/1601-1700info.gif"

voltaire = new Image
voltaire.src = "/images/scirc/1701-1750_off.jpg"
voltaireon = new Image
voltaireon.src = "/images/scirc/1701-1750_on.jpg"
voltaireonr = new Image
voltaireonr.src = "/images/scirc/1701-1750_onr.jpg"
voltaireinfo = new Image
voltaireinfo.src = "/images/scirc/1701-1750info.gif"

washington = new Image
washington.src = "/images/scirc/1751-1800_off.jpg"
washingtonon = new Image
washingtonon.src = "/images/scirc/1751-1800_on.jpg"
washingtononr = new Image
washingtononr.src = "/images/scirc/1751-1800_onr.jpg"
washingtoninfo = new Image
washingtoninfo.src = "/images/scirc/1751-1800info.gif"

napoleon = new Image
napoleon.src = "/images/scirc/1801-1850_off.jpg"
napoleonon = new Image
napoleonon.src = "/images/scirc/1801-1850_on.jpg"
napoleononr = new Image
napoleononr.src = "/images/scirc/1801-1850_onr.jpg"
napoleononl = new Image
napoleononl.src = "/images/scirc/1801-1850_onl.jpg"
napoleoninfo = new Image
napoleoninfo.src = "/images/scirc/1801-1850info.gif"

lincoln = new Image
lincoln.src = "/images/scirc/1851-1899_off.jpg"
lincolnon = new Image
lincolnon.src = "/images/scirc/1851-1899_on.jpg"
lincolnonl = new Image
lincolnonl.src = "/images/scirc/1851-1899_onl.jpg"
lincolninfo = new Image
lincolninfo.src = "/images/scirc/1851-1899info.gif"

titanic = new Image (110,18);
titanic.src = "/images/scirc/1900-1919_off.jpg"
titanicinfo = new Image
titanicinfo.src = "/images/scirc/1900-1919info.gif"
titanicon = new Image
titanicon.src = "/images/scirc/1900-1919_on.jpg"

chaplin = new Image
chaplin.src = "/images/scirc/1920-1929_off.jpg"
chaplinon = new Image
chaplinon.src = "/images/scirc/1920-1929_on.jpg"
chaplinonl = new Image
chaplinonl.src = "/images/scirc/1920-1929_onl.jpg"
chaplininfo = new Image
chaplininfo.src = "/images/scirc/1920-1929info.gif"

depression = new Image
depression.src = "/images/scirc/1930-1939_off.jpg"
depressionon = new Image
depressionon.src = "/images/scirc/1930-1939_on.jpg"
depressioninfo = new Image
depressioninfo.src = "/images/scirc/1930-1939info.gif"

pearlharbor = new Image
pearlharbor.src = "/images/scirc/1940-1949_off.jpg"
pearlharboron = new Image
pearlharboron.src = "/images/scirc/1940-1949_on.jpg"
pearlharboronl = new Image
pearlharboronl.src = "/images/scirc/1940-1949_onl.jpg"
pearlharborinfo = new Image
pearlharborinfo.src = "/images/scirc/1940-1949info.gif"

howdydoody = new Image
howdydoody.src = "/images/scirc/1950-1959_off.jpg"
howdydoodyon = new Image
howdydoodyon.src = "/images/scirc/1950-1959_on.jpg"
howdydoodyonl = new Image
howdydoodyonl.src = "/images/scirc/1950-1959_onl.jpg"
howdydoodyinfo = new Image
howdydoodyinfo.src = "/images/scirc/1950-1959info.gif"

doctorking = new Image
doctorking.src = "/images/scirc/1960-1969_off.jpg"
doctorkingon = new Image
doctorkingon.src = "/images/scirc/1960-1969_on.jpg"
doctorkingonr = new Image
doctorkingonr.src = "/images/scirc/1960-1969_onr.jpg"
doctorkinginfo = new Image
doctorkinginfo.src = "/images/scirc/1960-1969info.gif"

trickydick = new Image
trickydick.src = "/images/scirc/1970-1979_off.jpg"
trickydickon = new Image
trickydickon.src = "/images/scirc/1970-1979_on.jpg"
trickydickinfo = new Image
trickydickinfo.src = "/images/scirc/1970-1979info.gif"

computers = new Image
computers.src = "/images/scirc/1980-1989_off.jpg"
computerson = new Image
computerson.src = "/images/scirc/1980-1989_on.jpg"
computersonr = new Image
computersonr.src = "/images/scirc/1980-1989_onr.jpg"
computersinfo = new Image
computersinfo.src = "/images/scirc/1980-1989info.gif"

jordan = new Image
jordan.src = "/images/scirc/1990-present_off.jpg"
jordanon = new Image
jordanon.src = "/images/scirc/1990-present_on.jpg"
jordanonl = new Image
jordanonl.src = "/images/scirc/1990-present_onl.jpg"
jordaninfo = new Image
jordaninfo.src = "/images/scirc/1990-presentinfo.gif"
---------------------------------------------------------*/

//********  CHRONOLOGY (TIMELINE) GRAPHICS *********//

info_off = new Image (110,18);
info_off.src = "/images/scirc/bgbig.gif"

bc = new Image (110,18);
bc.src = "/images/scirc/bc_off.jpg"
bcinfo = new Image
bcinfo.src = "/images/scirc/bcinfo.gif"
bcon = new Image
bcon.src = "/images/scirc/bc_on.jpg"
bconr = new Image
bconr.src = "/images/scirc/bc_onr.jpg"

bcwheat = new Image
bcwheat.src = "/images/scirc/1-500_off.jpg"
bcwheaton = new Image
bcwheaton.src = "/images/scirc/1-500_on.jpg"
bcwheatinfo = new Image
bcwheatinfo.src = "/images/scirc/1-500info.gif"

dioscorides = new Image
dioscorides.src = "/images/scirc/501-1000_off.jpg"
dioscorideson = new Image
dioscorideson.src = "/images/scirc/501-1000_on.jpg"
dioscoridesonl = new Image
dioscoridesonl.src = "/images/scirc/501-1000_onl.jpg"
dioscoridesonr = new Image
dioscoridesonr.src = "/images/scirc/501-1000_onr.jpg"
dioscoridesinfo = new Image
dioscoridesinfo.src = "/images/scirc/501-1000info.gif"

astronomer = new Image
astronomer.src = "/images/scirc/1001-1500_off.jpg"
astronomeron = new Image
astronomeron.src = "/images/scirc/1001-1500_on.jpg"
astronomeronl = new Image
astronomeronl.src = "/images/scirc/1001-1500_onl.jpg"
astronomerinfo = new Image
astronomerinfo.src = "/images/scirc/1001-1500info.gif"

fibonacci = new Image
fibonacci.src = "/images/scirc/1501-1600_off.jpg"
fibonaccion = new Image
fibonaccion.src = "/images/scirc/1501-1600_on.jpg"
fibonaccionr = new Image
fibonaccionr.src = "/images/scirc/1501-1600_onr.jpg"
fibonacciinfo = new Image
fibonacciinfo.src = "/images/scirc/1501-1600info.gif"

newton = new Image
newton.src = "/images/scirc/1601-1700_off.jpg"
newtonon = new Image
newtonon.src = "/images/scirc/1601-1700_on.jpg"
newtononr = new Image
newtononr.src = "/images/scirc/1601-1700_onr.jpg"
newtoninfo = new Image
newtoninfo.src = "/images/scirc/1601-1700info.gif"

linnaeus = new Image
linnaeus.src = "/images/scirc/1701-1750_off.jpg"
linnaeuson = new Image
linnaeuson.src = "/images/scirc/1701-1750_on.jpg"
linnaeusonr = new Image
linnaeusonr.src = "/images/scirc/1701-1750_onr.jpg"
linnaeusinfo = new Image
linnaeusinfo.src = "/images/scirc/1701-1750info.gif"

halley = new Image
halley.src = "/images/scirc/1751-1800_off.jpg"
halleyon = new Image
halleyon.src = "/images/scirc/1751-1800_on.jpg"
halleyonr = new Image
halleyonr.src = "/images/scirc/1751-1800_onr.jpg"
halleyinfo = new Image
halleyinfo.src = "/images/scirc/1751-1800info.gif"

farraday = new Image
farraday.src = "/images/scirc/1801-1850_off.jpg"
farradayon = new Image
farradayon.src = "/images/scirc/1801-1850_on.jpg"
farradayonr = new Image
farradayonr.src = "/images/scirc/1801-1850_onr.jpg"
farradayonl = new Image
farradayonl.src = "/images/scirc/1801-1850_onl.jpg"
farradayinfo = new Image
farradayinfo.src = "/images/scirc/1801-1850info.gif"

mendeleev = new Image
mendeleev.src = "/images/scirc/1851-1899_off.jpg"
mendeleevon = new Image
mendeleevon.src = "/images/scirc/1851-1899_on.jpg"
mendeleevonl = new Image
mendeleevonl.src = "/images/scirc/1851-1899_onl.jpg"
mendeleevinfo = new Image
mendeleevinfo.src = "/images/scirc/1851-1899info.gif"

chromosome = new Image (110,18);
chromosome.src = "/images/scirc/1900-1919_off.jpg"
chromosomeinfo = new Image
chromosomeinfo.src = "/images/scirc/1900-1919info.gif"
chromosomeon = new Image
chromosomeon.src = "/images/scirc/1900-1919_on.jpg"

lindbergh = new Image
lindbergh.src = "/images/scirc/1920-1929_off.jpg"
lindberghon = new Image
lindberghon.src = "/images/scirc/1920-1929_on.jpg"
lindberghonr = new Image
lindberghonr.src = "/images/scirc/1920-1929_onr.jpg"
lindberghinfo = new Image
lindberghinfo.src = "/images/scirc/1920-1929info.gif"

planets = new Image
planets.src = "/images/scirc/1930-1939_off.jpg"
planetson = new Image
planetson.src = "/images/scirc/1930-1939_on.jpg"
planetsonl = new Image
planetsonl.src = "/images/scirc/1930-1939_onl.jpg"
planetsinfo = new Image
planetsinfo.src = "/images/scirc/1930-1939info.gif"

atomicbomb = new Image
atomicbomb.src = "/images/scirc/1940-1949_off.jpg"
atomicbombon = new Image
atomicbombon.src = "/images/scirc/1940-1949_on.jpg"
atomicbombonl = new Image
atomicbombonl.src = "/images/scirc/1940-1949_onl.jpg"
atomicbombinfo = new Image
atomicbombinfo.src = "/images/scirc/1940-1949info.gif"

univac = new Image
univac.src = "/images/scirc/1950-1959_off.jpg"
univacon = new Image
univacon.src = "/images/scirc/1950-1959_on.jpg"
univaconl = new Image
univaconl.src = "/images/scirc/1950-1959_onl.jpg"
univacinfo = new Image
univacinfo.src = "/images/scirc/1950-1959info.gif"

moonwalk = new Image
moonwalk.src = "/images/scirc/1960-1969_off.jpg"
moonwalkon = new Image
moonwalkon.src = "/images/scirc/1960-1969_on.jpg"
moonwalkonr = new Image
moonwalkonr.src = "/images/scirc/1960-1969_onr.jpg"
moonwalkinfo = new Image
moonwalkinfo.src = "/images/scirc/1960-1969info.gif"

brainscan = new Image
brainscan.src = "/images/scirc/1970-1979_off.jpg"
brainscanon = new Image
brainscanon.src = "/images/scirc/1970-1979_on.jpg"
brainscaninfo = new Image
brainscaninfo.src = "/images/scirc/1970-1979info.gif"

sallyride = new Image
sallyride.src = "/images/scirc/1980-1989_off.jpg"
sallyrideon = new Image
sallyrideon.src = "/images/scirc/1980-1989_on.jpg"
sallyrideonr = new Image
sallyrideonr.src = "/images/scirc/1980-1989_onr.jpg"
sallyrideinfo = new Image
sallyrideinfo.src = "/images/scirc/1980-1989info.gif"

hubble = new Image
hubble.src = "/images/scirc/1990-present_off.jpg"
hubbleon = new Image
hubbleon.src = "/images/scirc/1990-present_on.jpg"
hubbleonl = new Image
hubbleonl.src = "/images/scirc/1990-present_onl.jpg"
hubbleinfo = new Image
hubbleinfo.src = "/images/scirc/1990-presentinfo.gif"

function img_act (tag) {
	document [tag].src = eval(tag + "h.src");
}

function img_inact (tag) {
    document [tag].src = eval(tag + ".src");
}