        private void button1_Click(object sender, EventArgs e)
        {
            label1 .Text  = "Construced with " +
                "\n t1:  all argument defaulted " +
                "\n " + t1.ToUniversalString() +
                "\n " + t1.ToStandardString();

            label1.Text += "\n\n Construced with " +
                "\n t2: hour specified and other default  " +
                "\n\t\t " + t2.ToUniversalString() +
                "\n\t\t " + t2.ToStandardString();

            label1.Text += "\n\n Construced with " +
                "\n t3: hour, and minute  specified and second default  " +
                "\n\t\t " + t3.ToUniversalString() +
                "\n\t\t " + t3.ToStandardString();

            label1.Text += "\n\n Construced with " +
                "\n t4: all specified " +
                "\n " + t4.ToUniversalString() +
                "\n " + t4.ToStandardString();
            
        }
