THE HAKVEIAN ORATION. 731 



his seventy-fourth year, we should not have had the following 

 statement at page 9 of his book : 'I have conceived that the arteries 

 contained air in an uncombined state, which may assist in keeping 

 them distended, and in facilitating the circulation ; but I have not 

 been able to prove it.' The fact that Harvey performed experi- 

 ments in the way of injection may be unknown to many persons 

 who are too well informed to conceive that the arteries may or 

 can, compatibly with the carrying on of any circulation, contain 

 air in an uncombined state ; for these experiments are not to be 

 found recorded either in the treatise ' De Motu Cordis ' or in 

 either of the two letters to Riolanus ; which two compositions were, 

 in the older editions of Harvey's works, printed as three parts of 

 a single treatise, under the names of ' Exercitatio Anatomica i. De 

 Motu Cordis,' etc., 'Exercitatio Anatomica ii. De Circulatione 

 Sanguinis,' and 'Exercitatio Anatomica iii. De Circulatione San- 

 guinis;' and were, till the appearance of the College of Physicians' 

 edition in 1766, the only published^, as they are still the best 



^ The statement made (by Dr. Akenside ; see Pettigrew, 'Medical Portrait Gallery,* 

 Preface, p. 7, citing Dr. F. Hawkins) in the Praefatio to the College of Piiysicians' 

 edition of Harvey's works, to the effect that only two of Harvey's Letters had been 

 published prior to the year 1 766, is not correct. Horstius, as Harvey's words in the 

 'Epistola Sexta,' p. 631 ('Harveii Opera,' ed. 1766), show, when read in connexion 

 with the Epistola immediately preceding it, received three letters from Harvey. By 

 consulting Horstius' work referred to by Dr. Akenside, I. c, I found at pp. 61-65 the 

 letter, which appears in our edition as ' Epistola Tertia responsoria Morisono,' pub- 

 lished by Horstius in 1656 with the omission of the first six and a half, and also of the 

 last three and a half lines. These lines Harvey had doubtless ordered his amanuensis 

 — a functionary of great importance to one who wrote so bad a hand (see p. 165, ed. 

 1766, or Harvey's own autograph MS., No. 486, Sloane Coll., British Museum)— to 

 omit when he bade him copy and send to Horstius, 'eadem quae antea medico cuidam 

 Parisiensi (sc. Morisono) responderat.' Horstius does not publish Harvey's letter 

 (the 'Epistola Quinta' of our edition) of date Feb. i, 1654-5, but appends the last 

 letter of the three (the 'Epistola Sexta' of our edition) to his own answer to Harvey's 

 earlier communication. I shall henceforward refer to the College of Physicians' 

 edition of Harvey's works as 'ed. 1766,' and to Dr. Willis' most valuable translation 

 of them, published by the Sydenham Society in 1847, as ' ed. Willis.' I throw^ out as 

 a topic for future discussion the question whether Dr. Willis is right in following the 

 editions of Harvey's writings of an earlier date than 1 766, in retaining the negative 

 in the sentence (at p. 131 in both his edition and in that of 1766) in the second 

 epistle to Riolanus which refers to the Critias of Plato. I think Dr. Willis is right, 

 and that Dr. Lawrence was wrong ; but to do this it is necessary to sacrifice Harvey's 

 credit for knowledge of Plato whilst vindicating the consecutiveness of his reasoning. 

 Harvey himself would probably have accepted this alternative. It is right to add, 

 however, that so far as my reading of the edition of 1766 has carried me, I have come 

 upon no other case where I have been forced to think that Dr. Lawrence may have 

 blundered. 



