‘Mr. Watt has made two small improvements in the steam-engine.[13] [These are minutely described.] ... I have attended Dr. Black’s lectures. His doctrine of latent heat is the only thing I have yet heard that is altogether new. And indeed I look upon it as a very great discovery.... I have not met with any botanists here. Our College is considerably more crowded than it was last session. My class indeed is much the same as last year, but all the rest are better. I believe the number of our students of one kind or another may be between four and five hundred. But the College at Edinburgh is increased this year much more than we are. The Moral Philosophy class there is more than double ours. The Professor, Ferguson, is indeed, as far as I can judge, a man of a noble spirit, of very elegant manners, and has an uncommon flow of eloquence. I hear he is about to publish, I don’t know under what title, a natural history of man; exhibiting a view of him in the savage state, and in the several successive states of pasturage, agriculture, and commerce. Our Society [Senate] is not so harmonious as I wish. Schemes of interest, pushed by some and opposed by others, are like to divide us into parties, and perhaps engage us in law suits. Mrs. Reid, Pegie, and I, have all had a severe cold and cough. I have been keeping the house these two days in order to get the better of it.’
On ‘December 30th, 1765,’ a less sanguine view appears, in a letter to Andrew Skene:—
‘I assure you I can rarely find an hour which I am at liberty to dispose of as I please. The most disagreeable thing in the teaching part is to have a great number of stupid Irish teagues, who attend classes for two or three years to qualify them for teaching schools or being dissenting teachers. I preach to them as St. Francis did to the fishes. I don’t know what pleasure he had in his audience; but I should have none in mine, if there were not in it a mixture of reasonable creatures. I confess I think there is a smaller proportion of these in my class this year than there was the last. I have long been of the opinion that, in a right constituted College, there ought to be two professors for each class—one for the dunces, and another for those who have parts. The province of the former would not be the most agreeable, but perhaps it would require the greatest talents, and therefore ought to be accounted the post of honour. There is no part of my time more disagreeably spent than that which is spent in college meetings; and I should have been attending one at this moment if a bad cold I have got had not furnished me with an excuse. These meetings are become more disagreeable by an evil spirit of party that seems to put us in a ferment, and I am afraid will produce bad consequences. The temper of our northern Colonies makes mercantile people here look very grave. It is said that the effects in these colonies belonging to this town amount to above £400,000.[14] The mercantile people are for suspending the Stamp-act, and redressing the grievances of the colonists.... In what light the House of Commons will view this matter I don’t know, but it seems to me one of the most important matters that have come before them. I wish often an evening with you, such as we have enjoyed in the days of former times, to settle the important affairs of Church and State, of Colleges and Corporations. I have found this the best expedient to think of them without melancholy and chagrin. And I think all that a man has to do in the world is to keep his temper and to do his duty. Mrs. Reid is tolerably well just now, but is often ailing.’
In a letter to Dr. David, in March 1766, he refers to the death of his early friend, John Stewart, the Mathematical Professor in Marischal College, and his companion in the English tour thirty years before:—
‘Mr. Stewart’s death affects me deeply. A sincere friendship, begun at twelve years of age, and continued to my time of life, without any interruption, cannot but give some pangs. You know his worth; yet it was shaded ever since you knew him by too great abstraction from the world. The former part of his life was more amiable and more social; but the whole was of a piece in virtue, candour, and humanity.... I have always regarded him as my best tutor, though of the same age with me. If the giddy part of my life was in any degree spent innocently and virtuously, I owe it to him more than to any human creature; for I could not but be virtuous in his company, and I could not be so happy in any other. But I must leave this pleasing melancholy subject. He is happy; and I shall often be happy in the remembrance of our friendship; and I hope we shall meet again.’
A minute account of Black’s theory of latent heat follows.
Later in the same year, Black was called to the Chair of Chemistry in Edinburgh, which he filled for nearly thirty years, and in Reid’s letters to the Skenes there is much about candidates for the vacant office in Glasgow, with a suggestion that David Skene should himself enter the lists. ‘There is a great spirit of inquiry among the young people here. Literary merit is much regarded; and I conceive the opportunities a man has of improving himself are much greater here than at Aberdeen. The communication with Edinburgh is easy. One goes in the stage coach to Edinburgh before dinner; has all the afternoon there, and returns to dinner at Glasgow next day; so that if you have any ambition to get into the College of Edinburgh (which I think you ought to have), I conceive Glasgow would be a good step.’
The appeal was ineffectual. Meantime his own appointment, as an ‘examinator’ of candidates for the vacant Mathematical Chair in Marischal College, made a visit to Aberdeen necessary, as anticipated in a letter on ‘May 8th’:—
‘My class will be over in less than a month, and by that time I shall be glad to have some respite. I hope to have the pleasure of seeing my friends in Aberdeen in August, if not sooner. We have had a stronger College this year than ever before. We have been remarkably free from riots and disorders among the students; and I did not indeed expect that 350 young fellows could have keen kept quiet for so many months with so little trouble.... You’ll say to all this that cadgers are aye speaking of crooksaddles. I think so they ought; besides, I have nothing else to say to you, and have had no time to think of anything but my crooksaddles for seven months past. When the session’s over, I must rub up my mathematics against the month of August. There is one candidate for your profession of mathematics to go from this College; and if your College get a better man, or a better mathematician, they will be very lucky.[15] I am so sensible of the honour the Magistrates have done me in naming me to be one of the examinators, that I will not decline it, though I confess I like the honour better than the office.’
In the autumn of 1766 Reid exchanged the house in the Drygate for an official residence in the Professors’ Court of the Old College. This appears in a letter to Dr. Andrew Skene on December 17th:—