In reviewing what has now been stated respecting the diagnosis of pregnancy, it will be observed that we have enumerated four symptoms, which must be looked upon as perfectly diagnostic of this condition, and in the accuracy and certainty of which we may place the fullest confidence: two may be recognised at an early period by means of auscultation, viz. the sounds produced by the movements of the foetus and by the pulsations of its heart; the two others are not appreciable until a later period, and are afforded by manual examination, viz. the being able to feel the head of the foetus per vaginam, and its movements through the abdominal parietes. The next in point of value after these are the changes in the os and cervix uteri, those connected with the formation of the areola in the breasts, and, at a somewhat later period, the sound of the uterine circulation, changes, which, although they cannot separately be entirely depended upon, are nevertheless symptoms of very great importance in the diagnosis of pregnancy. Two other signs of pregnancy have also been mentioned, viz. the appearance of a peculiar deposite in the urine as described by M. Nauche, or rather by Savonarola (Montgomery, _op. cit._ p. 157.,) and the purple or violet appearance of the mucous membrane lining the vagina and os externum, as described by Professor Kluge of the Charité at Berlin, and by M. M. Jacquemin, Parent Duchatelet, &c. of Paris. With regard to the first, which is an old popular symptom of pregnancy, there is too much variety in the appearances of the urine, depending on general health, diet, temperature, &c., to enable us to place much confidence in any change of this sort. "I have myself tried it," says Dr. Montgomery, "in several instances, and the result of my trials has been this:--In some instances no opinion could be formed as to whether the peculiar deposite existed or not, on account of the deep colour and turbid condition of the urine; but in the cases in which the fluid was clear, and pregnancy existing, the peculiar deposite was observed in every instance. Its appearance would be best described by saying that it looks as if a little milk had been thrown into the urine, and having sunk through it had partly reached the bottom, while a part remained suspended and floating through the lower part of the fluid in the form of a whitish semi-transparent filmy cloud." (_Op cit._ p. 157.)[44] The purple colour of the vaginal entrance appears, from the extensive experience of the above-mentioned authors, to be a pretty constant change produced by the state of pregnancy; it probably occurs at a very early period. How far a similar tinge is produced by the state of uterine congestion immediately before a menstrual period, we are unable to say; at any rate, the character of the examination itself must ever be sufficient to preclude its being practised in this country.