“So great,” says Dr. Currie, “are the difficulties of tracing out the hidden causes of the disorders to which this frame of ours is subject, that the most candid of the profession have allowed and lamented how unavoidably they are in the dark; so that the best medicines, administered by the wisest heads, shall often do the mischief they intend to prevent.” There are more reasons for this than Dr. Currie has here assigned. For not only are many of the diseases which flesh is heir to, obscure in their causes, difficultly distinguishable by their symptoms, and altogether mysterious in their effect upon the system, but constitutions may be as different as tempers, and their varieties may be as many and as great as those of the human countenance. Thus it is explained wherefore the treatment which proves successful with one patient, should fail with another, though precisely in the same stage of the same disease. Another and not unfrequent cause of failure is that the life of a patient may depend as much upon administering the right remedy at the right point of time, as the success of an alchemist was supposed to do upon seizing the moment of projection. And where constant attendance is not possible, or where skill is wanting, it must often happen that the opportunity is lost. This cause would not exist in the Columbian Infirmary, where the ablest Physicians would be always within instant call, and where the Beguines in constant attendance would have sufficient skill to know when that call became necessary. A ship-captain, the Doctor used to say, when he approaches the coast of France from the Bay of Biscay, or draws near the mouth of the British Channel, sends down the lead into the sea, and from the appearance of the sand which adheres to its tallowed bottom, he is enabled to find upon the chart where he is, with sufficient precision for directing his course. Think, he would say, what an apparently impossible accumulation of experience there must have been, before the bottom of that sea, everywhere within soundings could be so accurately known, as to be marked on charts which may be relied on with perfect confidence! No formal series of experiments was ever instituted for acquiring this knowledge; and there is nothing in history which can lead us to conjecture about what time sailors first began to trust to it. The boasted astronomy of the Hindoos and Egyptians affords a feebler apparent proof in favour of the false antiquity of the world, than might be inferred from this practice. Now if experience in the Art of Healing had been treasured up with equal care, it is not too much to say that therapeutics might have been as much advanced, as navigation has been by preserving the collective knowledge of so many generations?[1]