He is generally considered one of the most important ichthyologists of the 18th century. Some knowledge of Hebrew and rabbinical literature enabled him, however, to obtain a teacher"s position in the house of a Jewish surgeon in Hamburg. Here he learned German thoroughly and mastered some Latin, taking up also the study of anatomy.
Scientific enthusiasm being thus aroused, Bloch went to Berlin, where, with remarkable zeal, he devoted himself to the study of all branches of natural science and medicine, being supported by some relatives.
"After taking the degree of Doctor of Medicine at Frankfort-on-the-Oder in 1747, he settled in Berlin, where he established himself as a physician. He found means to collect there a valuable museum of objects from all the kingdoms of nature, as well as an extensive library.
His first work of importance was an essay on the different species of worms found in the bodies of other animals, which gained the prize offered by the Academy of Copenhagen. Many of his papers on different subjects of natural history, comparative anatomy, and physiology, were published in the collections of the various academies of Germany, Holland, and Russia, particularly in that of the Friendly Society of Naturalists at Berlin."
"In 1797 he paid a visit to Paris, in order to examine the large collections of such subjects of natural history as had been inaccessible to him on the shores of the Baltic Sea, and he returned to Berlin by way of Holland.
His health, which had hitherto been unimpaired, began to decline.
He went to Carlsbad for its recovery, but his constitution was exhausted." He died in Carlsbad on August 6, 1799.
German Academy of Sciences Leopoldina.