Born in Warwick the eldest son of Joseph Baly. His brother was Price Richard Baly, the engineer. Educated at the Grammar school in Warwick and subsequently at St. George's Hospital, London and the infirmary at Shrewsbury. After graduating as a Doctor of Medicine he moved to Paris before returning to England, first in Leamington and then in London where he 'secured a very large practice and formed the friendship of many scientific men of the day, including the chiefs at the British Museum'. After his health broke down he returned to Warwick in about 1868 and remained there until his death in 1890. At various times he was Medical Officer of Health for Leamington and also medical officer of the Union Infirmary. He also served as a J.P. and was Honorary Curator of the Warwick Museum.
Baly's interest in entomology appears to have been stimulated initially by his work on microscopy. David Sharp recorded that about 1850 'he visited Mr S. Stevens, in Bloomsbury Street, in search of objects for his microscope, and he purchased a small collection of Indian Hymenoptera. He entered into a correspondence with Mr H.W. Bates, who was then in the Amazon Valley, and in the course of this informed Mr Bates that the marvels of insect structure revealed by his microscope led him to devote himself more exclusively to entomology. At that time the collections made by Wallace in the Malay Archipelago and by Bates in the Amazon Valley were arriving in this country and Baly having a good series of the phytophagous Coleoptera from them, found full occupation for his leisure time...’ (Ent, 23, 1890, 199).
From this beginning Baly went on to become the foremost worker on this group of his day. He amassed a huge collection and described enormous numbers of new species in a series of articles and books which commenced with his 'Monograph of the Australian species of Chrysomela, Phyllocharis and allied genera’ in Trans.ent.Soc.Lond., (2)3, 1855, 170-186,241-263, and ended with descriptions of new species of Galerucinae in the year of his death. His best known publications are probably his Catalogue of the Hispidae in the British Museum (1858) and the 'Phytophaga Malayana, a revision of the phytophagous beetles of the Malay archipelago, with descriptions of the new species collected by Alfred R. Wallace' in Trans.ent.Soc.Lond., 1865, 1-76 and 1867, 77-300.
Baly’s collection was purchased in parts by the NHM between 1880 and 1905 and amounted in all to some 28,000 specimens including more than 1,200 types. Many Coleoptera had earlier (1855-56) been exchanged by the Museum for Baly specimens and other specimens purchased from him in 1860. Some Coleoptera and Hymenoptera were sold by Stevens on 25 November 1890. Insects other than beetles were purchased by the HDO in 1857 and March 1877.
Apart from the account by Sharp already mentioned, Gilbert (1977) lists a further five references. (MD 9/01, 6/18)