function calc_sq(){
		var dimW = eval(document.Calc_form.W.value);
		var dimL = eval(document.Calc_form.L.value);
		document.Calc_form.rect_low_end.value =
			Math.round
			(dimW * dimL * eval(.50));
		document.Calc_form.rect_high_end.value =
			Math.round
			(dimW * dimL * eval(.73));
		var a = document.Calc_form.rect_low_end.value;
		var b = document.Calc_form.rect_high_end.value;	
	}

	function calc_arch(){
		var dimR = eval(document.Calc_form.R.value);
		document.Calc_form.arch_low_end.value =
			Math.round
			(dimR * dimR * eval(1.57) * eval(.50));
		document.Calc_form.arch_high_end.value =
			Math.round
			(dimR * dimR * eval(1.57) * eval(.73));
		var c = document.Calc_form.arch_low_end.value;
		var d = document.Calc_form.arch_high_end.value;	
	}