For example biology and physics are connected by the use of the microscope.

Still, I may safely assert that a technical description of the uses of the microscope in biology is not part of the philosophy of the sciences.

Again, you cannot abandon the later clause of the definition; namely that referring to the relations between the sciences, without abandoning the explicit reference to an ideal in the absence of which philosophy must languish from lack of intrinsic interest.

That ideal is the attainment of some unifying concept which will set in assigned relationships within itself all that there is for knowledge, for feeling, and for emotion.
That far off ideal is the motive power of philosophic research; and claims allegiance even as you expel it.

The philosophic pluralist is a strict logician; the Hegelian thrives on contradictions by the help of his absolute; the Mohammedan divine bows before the creative will of Allah; and the pragmatist will swallow anything so long as it 'works.' The mention of these vast systems and of the age-long controversies from which they spring, warns us to concentrate.