\documentclass{article}
 
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{tikz}
\usepackage{scalefnt}
 
\begin{document}
\pagestyle{empty}

\def\linetick#1#2{
  \draw[-] ({#1},3.075) node [anchor=south] {#2} -- (#1,2.925) ;
}

\def\microscope#1{
  \draw [thick,-         ] (#1 -0.25,2.15) -- (#1+0,3) -- (#1 +0.25,2.15) ;
  \draw [thick,fill=white] (#1 +0.00,1.50) circle (1) ;  
  \fill [white           ] (#1 -0.25,2.15) -- (#1+0,3) -- (#1 +0.25,2.15) ;
  \draw [thick,blue,->   ] (#1-0.95,1.5) -- (#1+0.95,1.5) ;
}

\def\microtick#1#2#3#4#5{
  \draw [-,#4] (#1+0.375*#2,1.6) node [anchor=#5,font=\small] {#3} -- (#1+0.375*#2,1.4) ;
}

\def\microhookright#1#2#3#4#5{
  \draw [->,#5] (#1+0.375*#2,1.3) to [out=210,in=-30] (#1+0.375*#3+0.05,1.3) ;
  \node [anchor=north,#5] at ({#1+0.375*(#2+#3)/2+0.05},{1.3-abs(#3-#2)/20}) {#4} ;
}

\def\microhookleft#1#2#3#4#5{
  \draw [->,#5] (#1+0.375*#2,1.3) to [out=-30,in=210] (#1+0.375*#3-0.05,1.3) ;
  \node [anchor=north,#5] at ({#1+0.375*(#2+#3)/2-0.05},{1.3-abs(#3-#2)/20}) {#4} ;
}

\begin {tikzpicture} [scale=2]
  \draw[blue,thick,->]      (-3.1,3) -- (4.1,3) coordinate (x axis);
  
  \linetick{-3}{$-3$}
  \linetick{-2}{$-2$}
  \linetick{-1}{$-1$}
  \linetick{ 0}{$ 0$}
  \linetick{+1}{$ 1$}
  \linetick{+2}{$ 2$}
  \linetick{+2.71}{$ r$}
  \linetick{+3}{$ 3$}
  \linetick{+4}{$ 4$}
  
  \microscope    {2.71}
  \microtick     {2.71}{-2}{\tiny $r-2\epsilon$}{blue}{south}
  \microtick     {2.71}{-1}{\tiny $r- \epsilon$}{blue}{south}
  \microtick     {2.71}{ 0}{$r$}{}{south}
  \microtick     {2.71}{ 1}{\tiny $r+ \epsilon$}{blue}{south}
  \microtick     {2.71}{ 2}{\tiny $r+2\epsilon$}{blue}{south}
  \microhookleft {2.71}{-2}{0}{\scriptsize $\operatorname{st}$}{red}  
  \microhookleft {2.71}{-1}{0}{}{red}  
  \microhookright{2.71}{ 1}{0}{}{red}
  \microhookright{2.71}{ 2}{0}{\scriptsize $\operatorname{st}$}{red}
  
  \microscope    {-1}
  \microtick     {-1}{-0.3}{$-1$}{}{south}
  \microtick     {-1}{ 0.7}{\tiny $-1+\epsilon$}{blue}{south}
  \microtick     {-1}{ 1.9}{\tiny $-1+\gamma$}  {blue}{south}
  \microtick     {-1}{-1.7}{\tiny $-1+\eta$}    {blue}{south}
  \microhookleft {-1}{-1.7}{-0.3}{\scriptsize $\operatorname{st}$}{red}  
  \microhookright{-1}{ 0.7}{-0.3}{}{red}
  \microhookright{-1}{ 1.9}{-0.3}{\scriptsize $\operatorname{st}$}{red} 
\end {tikzpicture}

\end{document}