  Typical reconstructions of historic heliospheric magnetic field (HMF) $B_{\rm
HMF}$ are based on the analysis of the sunspot activity, geomagnetic data or on
measurement of cosmogenic isotopes stored in terrestrial reservoirs like trees
($^{14}$C) and ice cores ($^{10}$Be). The various reconstructions of $B_{\rm
HMF}$ are however discordant both in strength and trend. Cosmogenic isotopes,
which are produced by galactic cosmic rays (GCRs) impacting on meteoroids and
whose production rate is modulated by the varying HMF convected outward by the
solar wind, may offer an alternative tool for the investigation of the HMF in
the past centuries. In this work, we aim to evaluate the long-term evolution of
$B_{\rm HMF}$ over a period covering the past twenty-two solar cycles by using
measurements of the cosmogenic $^{44}$Ti activity ($\tau_{1/2} = 59.2 \pm 0.6$
yr) measured in 20 meteorites which fell between 1766 and 2001. Within the
given uncertainties, our result is compatible with a HMF increase from
$4.87^{+0.24}_{-0.30}$ nT in 1766 to $6.83^{+0.13}_{-0.11}$ nT in 2001, thus
implying an overall average increment of $1.96^{+0.43}_{-0.35}$ nT over 235
years since 1766 reflecting the modern Grand maximum. The $B_{\rm HMF}$ trend
thus obtained is then compared with the most recent reconstructions of the
near-Earth heliospheric magnetic field strength based on geomagnetic, sunspot
number and cosmogenic isotope data.
