Shipwreck off the Spanish coast: a boy and an untamed Arab stallion the sole survivors. This promising situation, led up to by a logical sequence of events, is used in [The Black Stallion,] an adventure story whose outsize plot is curbed by a firm attention to the relationship between the hero, Alec Ramsay, an American high-school boy, and the stallion who comes to be known as the Black. (p. 3406)
[The subsequent books in the Black Stallion series] are essentially tales of a horse and its fortunes and at times Alec seems little more than a necessary link in the narrative. His character is lightly sketched and the decisions he has to make, about finishing at college and about the financial risks of starting a racing stud, are offered to the reader with little depth, as the necessary realistic backing for crucial scenes where the Black's ferocity or his astonishing speed are demonstrated. This is as it should be, of course. In these linked adventure stories, action comes first. Chicanery and business acumen in racing circles, domestic circumstances and personal relationships, are there to give substance to the action. Even the details of training, while they will be absorbing to any horse-lover, would become monotonous if it were not for the high moments of action. Walter Farley's style is not innocent of cliché and it is not particularly polished but it works admirably as a medium for fast event, for the speed of a race or a trial gallop or the chases and escapes in the desert. The energy of the Black Stallion books and their strong subject-matter have kept them in print since the 1940's and should guarantee them a further extension of published life. (pp. 3406-07)
Margery Fisher, "A Bundle of Old Favourites," in her Growing Point, Vol. 17, No. 4, November, 1978, pp. 3406-07.