\documentclass[a4paper, 12pt]{article}

\usepackage{array}
\usepackage{fixltx2e}
\usepackage[top=1in, bottom=1in, left=1in, right=1in]{geometry}
\usepackage[utf8]{inputenc}
\usepackage{hyperref} 
\usepackage{fancyhdr}		% for nice headers
\usepackage{etoolbox}
\usepackage{setspace}		% line spacing


\makeatletter 	% needed because there is an @ symbol in a command
\renewcommand*\l@section{\@dottedtocline{1}{1.5em}{2.3em}}
\makeatother 		% reset to normal interpretation

% Change the name of the TOC from 'Content' to 'Table of Contents'
\renewcommand{\contentsname}{Table of Contents}

%================================================%

\begin{document}
\pagenumbering{roman}
\thispagestyle{empty}
\doublespacing
\tableofcontents

\onehalfspacing
\newpage
\pagenumbering{arabic} 
\pagestyle{fancy}
\fancyhf{}
\lhead{\nouppercase{\leftmark}}
\rhead{\thepage}

\section{My first chapter}

\newpage

\section{Second chapter}

\newpage

\section*{Bibliography}
\markboth{Bibliography}{}
\pretocmd{\section}{\addtocontents{toc}{\addvspace{116pt}}}{}{}
\addcontentsline{toc}{section}{Bibl}


first book

second book

\end{document}