**Thus** **he** **devoted** **some** **attention** **to** **the** **quadrature** **of** **surfaces** **and** **the** **cubature** **of** **solids**, **which** **he** **accomplished**, **in** **some** **of** **the** **simpler** **cases**, **by** **an** **original** **method** **which** **he** **called** **the** "**Method** **of** **Indivisibles**"; **but** **he** **lost** **much** **of** **the** **credit** **of** **the** **discovery** **as** **he** **kept** **his** **method** **for** **his** **own** **use**,**while** **Bonaventura** **Cavalieri** **published** **a** **similar** **method** **which** **he** **himself** **had** **invented**.

**The** **Arithmetica** **infinitorum** **relates** **chiefly** **to** **the** **quadrature** **of** **curves** **by** **the** **so-called** **method** **of** **indivisibles** **established** **by** **Bonaventura** **Cavalieri** **in** 1629 (**see** **Infinitesimal** **Calculus**).

**The** **simple** **nature** **of** **the** **alkalies** **Lavoisier** **considered** **so** **doubtful** **that** **he** **did** **not** **class** **them** **as** **elements**, **which** **he** **conceived** **as** **substances** **which** **could** **not** **be** **further** **decomposed** **by** **any** **known** **process** **of** **analysis** - **les** **molecules** **simples** **et** **indivisibles** **qui** **composent** **les** **corps**.

**Torricelli**, **by** **employing** **the** "**method** **of** **indivisibles**," **deduced** **that** **the** **area** **was** **exactly** **three** **times** **that** **of** **the** **generating** **circle**; **this** **result** **had** **been** **previously** **established** **in** 1640 **in** **France** **by** **G**.

**Cavalieri'****s** " **indivisibles** " **into** **the** **infinitesimal** **calculus**, **all** **accomplished** **during** **the** 17th **century**, **immeasurably** **widened** **the** **scope** **of** **exact** **astronomy**.