The Margaret was built in Chepstow in 1829.  Female prisoners were transported to New South Wales on the Margaret in 1837, 1839 and 1840.
One hundred and sixty-six female prisoners and 44 children, as well as 57 free women and children, wives and daughters of convicts were embarked in Ireland in August 1839.
Surgeon George Todd Moxey
George Todd Moxey kept a Medical Journal from 20 July 1838 to 14 January 1839..........
He inspected the women at the jail in Dublin on 23 August 1838 prior to embarkation and was highly pleased at their clean and healthy appearance. Most of the prisoners were young and robust, the free women were more aged.
He remarked that the total number of women was 269, and the Margaret being a vessel of only 364 tons, conditions were crowded. He endeavoured to impress upon them the necessity for their own health and comfort of keeping their berth places clean, dry and airy and by issuing gratuities of tea and sugar to the cleanest and best regulated messes. He maintained strict although mild discipline and in a short time the women became a well behaved, obedient and orderly set of women. 
The Margaret departed Kingstown, Ireland on 1st September 1838 and came via the Cape touching there 14th November 1838.
The Margaret arrived in Port Jackson on 5 January 1839.
Notes and Links
1). Some of the free women and children who arrived on the Margaret can be found in Wives and Children of Irish Convicts Petitioned by Husbands and Fathers. CD-ROM. Central Coast Family History Society Inc. East Gosford, New South Wales. An index of this CD can be found on Ancestry.