22. Bar to decree for divorce a mensa et toro; but judicial separation obtainable by husband or wife.- No decree shall hereafter be made for a divorce a mensa et toro, but the husband or wife may obtain a decree of judicial separation, on the ground of adultery, or cruelty, or desertion without reasonable excuse for two years or upwards, and such decree shall have the effect of a divorce a mensa et toro under the existing law, and such other legal effect as hereinafter mentioned.