SECTION 1. Subsection (B) of Section one hundred eighty-two of the National Internal Revenue Code, as amended, is hereby further amended to read as follows:
"(B) On Occupation.—Annual taxes on occupation shall be collected as follows:
"(1) Seventy-five pesos:
"(a) Lawyers, medical practitioners, architects, interior decorators, certified public accountants, civil, electrical, chemical, mechanical, mining or sanitary engineers, insurance agents and sub-agents, customs brokers, marine surveyors, actuaries, registered master plumbers, veterinarians, dental surgeons, opticians, commercial aviators, professional appraisers or connoisseurs of tobacco and other domestic or foreign products, licensed ship masters and marine chief engineers;
"(b) Mechanical plant engineers, junior mechanical engineers and certified plant mechanics, unless he or she is a professional mechanical engineer and has paid the corresponding fixed tax for mechanical engineers.
"The term 'mechanical engineers', as used herein, means professional mechanical engineers as defined in Commonwealth Act Numbered Two hundred and ninety-four.
"(2) Fifty pesos:
"(a) Land surveyors, chief mates, marine second engineers, pharmacists, registered nurses, chiropodists, tatooers, masseurs, pelotaris, jockeys, professional actors or actresses, stage performers, hostesses, statisticians, dietitians, commercial stewards and stewardesses, flight attendants, insurance adjusters and embalmers;
"(b) Midwives, unless he or she is a registered nurse and has paid the corresponding fixed tax for nurses;
"(c) Chemists, unless he or she is a registered chemical engineer and has paid the corresponding fixed tax for chemical engineers;
"(d) Associate electrical engineers, unless he or she is a professional electrical engineer and has paid the corresponding fixed tax for electrical engineers;
"(e) Marine officer, unless he is a marine engineer or second engineer and has paid the corresponding fixed tax for marine engineers or second engineers.
"Every professional legally authorized to practice his profession, who has paid the corresponding annual privilege tax on professions as herein imposed, shall be entitled to practice the profession for which he has been duly qualified under the law, in all parts of the Philippines without being subject to any other tax, charge, license or fee for the practice of such profession: Provided, however, That they have paid to the office concerned the registration fees required by their respective professions: Provided, further, That any amount collected in excess of the rates in effect prior to January one, nineteen hundred and fifty-seven, shall be refunded or credited to the taxpayer concerned subject to the provisions of Section three hundred and nine of this Code: And provided, finally, That any such professional employed and performing duties in such professional capacities but without the permission to practice their profession during or after office hours to private or personal clienteles are hereby exempted from the payment of such annual occupational taxes."