Returning again to our note of the dependence of the present age on Ericsson, mention may be made of the blower for forcing the combustion in steam-boilers as a well-established feature of standard marine practice, and one absolutely essential to the development of the highest attainable speeds, such as are required in warships, and especially in those of the torpedo and modern “Destroyer” types.  Likewise the use of the fan for ventilation, as used by him in his early practice, has become a necessity of modern conditions both on naval and passenger ships, for the health and comfort of both passengers and crew.  His long series of experiments and his years of labor on air and other forms of “caloric” engine are only represented by the “Ericsson air-engine” now on the market, and having its fair share of service in locations where simplicity of operation and scarcity of water may naturally suggest its use.

Of his labors in connection with a solar engine, and with other questions which occupied much of the time of his closing years, we have but little direct result.  Others are at work on the idea of the solar engine, and it may be that a practicable solution of the problem will be found.

Ericsson’s lasting imprint on engineering practice, curious as it may seem, was made in his earlier and middle life, rather than in his later years, and we have even more in the way of permanent acquisition from his earlier than from his middle years.  This results from the fact that in middle life he was largely engaged on warship designs, admirably adapted to the needs of the time and to the possibilities of the age, but no longer suited to either, while in later life he no longer found it necessary to work at problems which would produce a direct financial return, and therefore interested himself in a variety of questions somewhat farther removed from the walks of every-day engineering practice than those with which he was occupied in earlier life.

In personality Ericsson possessed the most pronounced and self-centred characteristics.  Professionally he felt that to him had been granted a larger measure of insight than to others into the mysteries of nature as expressed in the laws of mechanics, and he was therefore little disposed to listen to the advice or criticism of those about him.  This was undoubtedly one of Ericsson’s most pronounced professional faults.  He did not realize that with all his insight into the laws of mechanics and all his capacity for applying these laws to the solution of the problems under consideration, he might well make some use of the work of his fellow-laborers in the same field.  So little disposed was he to thus use the work of others that a given device or idea which had been in previous use was often rejected and search made for another, different and original, even though it might involve only some relatively trivial part of the work.  He was simply unwilling to follow in the lead of others.