The examinations were very stressful. The terms of both oral and written exams had to be reported in advance to the Land Committee which also nominated the examination commissioner. For example, in January and February 1843 Doppler had to examine 256 students in 17 days, both in writing and orally, in arithmetic and algebra. The examinations took a minimum of six hours daily. The same number of students sat for the examination in "theoretical geometry" in June and July of the same year in a twelve day examination. Additionally in July and August it was necessary to examine 145 students in geodesy in eight days. ... In July 1847 Doppler orally examined 526 students in mathematics and 289 in geodesy.

The position of a point in space is perfectly determined when its distances from three coordinated planes are known.

In the elements of analytical and descriptive geometry, it is also shown, as is well known, that the position of the coordinate planes in relation to one another is entirely arbitrary, and that the position of a point in space can also be fixed differently; but in these developments the coordinate planes should always be assumed to be perpendicular to each other and only right-angled coordinates should be mentioned. In descriptive geometry, it is seldom a question of the absolute position of the various objects.

The chief object of this science is: the faithful representation of the most varied forms in their various combinations, and therefore the exact determination of the relative position of individual points under different circumstances its main task.

Preface

In my first essay on orthographic parallel perspective, I developed the principles of this projection method and attempted to shed more light on the various representations of tri-, di-, isometric and oblique projection, as well as the graphic operations on which they are based.

In some remarks on the methods of perspective projection hitherto known, I have endeavoured to point out the generality of orthographic parallel perspective and several circumstances worthy of consideration which enable the designer to produce a perspective picture of an object without a special expenditure of time and effort, depending on the wishes of the individual and the purpose of the executing drawing, - and thus speak for the advantageous applicability of this projection method.

In the same essay I mentioned that by means of the method of free shadow determination in the orthographic parallel perspective, similar to the pure perspective, being able to determine the shadow on any object not infrequently with little effort and with visible advantages over the hitherto customary method of construction.

The construction of shadows for orthogonal and central projections can be found comprehensively treated in many works, but there is still a lack of an implementation of the same for a parallel perspective without the aid of the orthogonal projections of the shadow of an object.

I therefore tried to fill this gap and, in the present work, to deal briefly with the most essential of the free definition of the shadow in its application to the orthogonal or orthographic parallel perspective that I proposed in 1850 and was favourably received by the technical public.

Individual tasks involved in determining shadows were given special consideration insofar as they can be treated as problems of descriptive geometry.

Prague, 20 January 1855.

According to contemporary reports, Professor Skuherský explained things in a very engaging and understandable way. Also with his listeners, who in the vast majority of cases liked the subject, he established lasting friendly relations with many of them.

On his travels in Western Europe and England, Professor Skuherský met prominent workers in descriptive geometry, learnt French and English, and continued to emphasise the need to know foreign languages. He focused his extracurricular activities first on alleviating the misery of the poor technical students, so at the beginning of the 1860-61 academic year, thanks to him, a fund was set up for the providing of free lunches, which was organised by an elected student committee.

The whole of Prague proved with their participation in his funeral how they respected this man. The funeral procession came out of his house No. 831 on the corner of Jindrisska Street and Wenceslas Square opposite today's Polish Cultural Centre. It was attended by all organisations and associations in which Professor Skuherský had been active, and also those he had supported. He was buried in the Olsany cemetery ... .